Low Carb Diet Macros Not Keto

Low Carb Diet Macros Not Keto

Keto Macros VS Low Carb Macros

Keto, AKA a ketogenic diet, is a way of eating that helps promote ketosis – the natural metabolic state when your body burns fat for fuel, instead of carbohydrates. Ketosis starts after you deplete carb stores and fill your plate instead with plenty of satiating fats and a moderate amount of protein. Not just any ratio of macros will work to get the benefits of ketosis. Through our expert research, The ZonePerfect Pros have found the purposeful, true keto macro blend for a keto lifestyle: 75% fat, 20% protein, and 5% carbs.

A low carb lifestyle cuts calories by limiting carbohydrates and replacing them with protein-rich foods and includes a variety of fat, vitamins, minerals, and fiber. The low carb lifestyle places less of an emphasis on fats (unlike keto) and focuses more on getting lean with a daily diet of high protein choices. The exact macros for a Low Carb diet are more flexible than keto; the ZonePerfect Pros recommend sticking to a ratio of: 15-25% carbs, 40-50% protein, 30-35% fat. With the extra dose of protein, this blend helps you fight hunger, gives you consistent energy, and nourishes your body so you can tone up and hit your goals.

Nutrition You Need for a Keto Lifestyle

Since Keto isn't a low-carb or "all the meat you can eat" type plan, it's important to seek out keto-approved foods. Find energy in fat sources such as coconut oil, ZonePerfect Keto shakes, vegetable oils, nuts, seeds, butter, avocado; and round out your plate with non-starchy vegetables (ie leafy greens), just enough protein from meat, vegetable sources, high-fat dairy, fish, poultry, eggs, and seafood; and a hint of berries or lower carb fruits and other foods that are rich in fiber, vitamins and minerals but also contain carbs.

Low Carb and the Power of Protein

Working hard to reach your low carb goals? Don't let your day be derailed by empty calories from refined grains, sugar fixes, and carb-rich foods. Stay focused by filling up on nourishing protein-rich foods! In our research, experts have found that eating small amounts of protein throughout the day – 15+ grams per sitting, 4-6x/day – helps to continuously protect and fuel muscles, fights off hunger, and supports your hard work to tone up and get lean.

Low Carb Diet Macros Not Keto

Source: https://zoneperfect.com/blog/low-carb-vs-keto

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Low Vitamin D Symptoms Skin

Low Vitamin D Symptoms Skin

What happens if your levels of vitamin D are low?

Vitamin D is sometimes known as the forgotten 'neurosteroid' and in fact, some people even classify this nutrient as a hormone that should give you a clue as to its importance! Although it's usually known for its relationship with calcium (vitamin D is essential for healthy calcium absorption) as we shall discover, vitamin D is also crucial for many other bodily functions such as your immune system, mood, sleep and possibly even your digestion!

Unlike vitamin C, which must be obtained through your diet, your body is capable of synthesising vitamin D – there's just one catch! Your body synthesises vitamin D when your skin is exposed to sunlight, a scarce commodity at the best of times here in the UK, let alone in the depths of autumn! This means that many of us are going to be more susceptible to having low levels of vitamin D in the next few months but could this impact your skin? Let's take a look at a few of the main symptoms of vitamin D deficiency to find out.

Poor immune function

This time of the year can be very trying for your immune system as it seems every bug and viral infection is out to get you - coughs, colds  and flus seem to be lurking everywhere! Unfortunately, vitamin D is quite important when it comes to supporting your immune function – it's even thought that healthy levels of vitamin D may help ward off colds and flus!¹

When your levels of vitamin D are low, you may find that your immune system becomes more vulnerable to these types of infections. In fact, studies have found that those suffering from illnesses such as the common cold or a respiratory tract infections like bronchitis often display low levels of vitamin D²

While a weak immune system can influence your skin indirectly by upsetting your sleep patterns, it can also have a more direct impact. You see, your skin relies on a healthy immune system to help eliminate any bacteria or pathogens that permeate your epidermis and, if your immune function is sluggish, these bugs may linger which can result in a flare-up, especially if you suffer from a condition such as acne or eczema!

Increased inflammation

Inflammation can be a huge problem for your skin – not only is it a major trigger for acne breakouts and eczema flare-ups, even in healthy skin it can cause swelling and redness. Well, it turns out vitamin D is involved in decreasing inflammation too! More specifically, research has found that low levels of the inflammatory marker, C-reactive protein, are associated levels of vitamin D.³

Unfortunately, when your levels of vitamin D are low it can mean that you're more prone to inflammation. Some studies have even found that sufferers with severe vitamin D deficiencies have higher levels of inflammatory markers which could potentially affect how their wounds heal.⁴If your body isn't able to repair any damage to your skin properly, this can have consequences, especially in cases of eczema!

This isn't the only problem though; low levels of vitamin D have been linked to Inflammatory Bowel Disease (IBD), an inflammatory condition which can inhibit your digestion and cause symptoms such as diarrhoea and bloating to manifest. It was found that IBD sufferers often exhibit low levels of vitamin D⁵ which makes sense given vitamin D's influence on inflammatory markers.

Since your skin often relies on a healthy digestive system, this again can cause problems, especially if the nutrients from your food aren't being absorbed properly or, in cases of constipation, if toxins and waste products are lingering in your body!

Fatigue

Do find that during the winter months you feel more sluggish and perpetually tired? As it turns out, low levels of vitamin D could again be responsible here. This is because the nutrient had been linked to Seasonal Affective Disorder (SAD), which can impact your mood and make you feel more run down during winter. It's also possible that vitamin D might have an impact on your sleep patterns too, further exacerbating the issue.

If you're feeling low and lacking in energy it can affect your skin in a number of ways – for a start, you might become more sedentary, which may impact your circulation. It's also possible you might be more tempted by the allure of sugary foods, relying on them to temporarily boost your energy levels and, finally, if you are sleep deprived, you may find yourself more susceptible to stress – all of these factors can easily affect your skin!

Decreased insulin sensitivity

Did you know that vitamin D is needed for normal insulin secretion? Insulin is a very important hormone when it comes to regulating your blood sugar levels, preventing that dreaded sugar crash which can sap all your energy! Vitamin D is thought to help by improving insulin sensitivity, making it easier for the hormone to transport sugar, or glucose, out of your bloodstream, storing it for later use.

If your body becomes less sensitive to insulin, it can cause sugar to linger for longer in your bloodstream. This means you experience a great high followed by a more intense low that could have you reaching for a sugar snack. I've already spoken at length about the unhealthy relationship sugar can have with your skin but, if you suffer from acne, this can be a real problem!

Who's vulnerable to vitamin D deficiency?

Okay, so vitamin D deficiency is quite common here in the UK thanks to our less than tropical climate. Winter in particular, can be a challenging as what little sun we are blessed with quickly disappears and most of the time we are going to work and coming home in darkness. However, there are certain groups of people that are more vulnerable than others, as I shall explain.

Over 50s – As you get older, your demand for vitamin D increases. Unfortunately, this increased demand often comes at a time when you're not as able to synthesise vitamin D. It also doesn't help that you are more likely to be sedentary or more prone to injury at this point.

Vegans & vegetarians – When the weather's bad, you might be tempted to try and increase your intake of vitamin D by eating more vitamin d rich foods. Unfortunately, most foods that contain this nutrient are derived from animals and, although many foods are now fortified with vitamin D, if you're vegan or vegetarian you could still be at risk of getting deficient.

Office workers – How many of you work in an office? The chances are that most of you have some type of job that requires you to spend most of your time inside, rather than outside. This means that, especially in winter, your chances of synthesising some vitamin D from the sun are particularly slim.

Those on certain types of medication – That's right, the type of medication you are taking can affect your stores of vitamin D. Corticosteroids in particular can affect how your body metabolises vitamin D, so you may wish to speak to your doctor if you have any concerns.

Sufferers of digestive disorders – If you suffer from a digestive disorder like IBS or Crohn's your body may struggle to absorb vitamin D properly, particularly if it's coming from your diet. This can cause a vicious cycle as low vitamin D levels can sometimes contribute to inflammation, as I discussed earlier.

So, as you can see, quite a few of us might be more susceptible to having low levels of vitamin D which begs the question, what can you do to avoid becoming deficient?

How can I increase my intake of vitamin D?

There are plenty of ways you can go about increasing your intake of vitamin D but let's start with the most basic.

Sunlight, as I've mentioned, is an essential source of vitamin D which is why you should try and capitalise on it as much as possible. Even in the midst of winter, it's important you still try to spend some time outside whether it's a brisk walk on your lunch break or, if you're more active, a 5K run. Now I understand that the last thing you probably feel like doing is going outside when it's freezing cold but just 10 minutes can make a real difference so ditch the car, wrap up warm and walk to the shops!

You could also try looking at your diet and incorporate more vitamin D-rich foods. Oily fish like salmon and sardines are good sources but, if you are vegan, you could try mushrooms or fortified foods like cereal and dairy-free milks.

However, Public Health England recently advised that during the winter months, we might want to consider a mild 400 IU (approximately 10mcg) vitamin D supplement.⁶  Generally this is enough, however, if you feel as though you are more at risk of a deficiency you could try a stronger supplement – it's believed that anything up to 1000IU is safe to take. Just take care though, many of the supplements on high street shelves often count double or triple this amount and, as our Nutritionist Emma discusses her blog, 'Are you getting too much vitamin D?' over-supplementing can be just as dangerous as a deficiency.

If you're looking to top up your vitamin D levels and fight fatigue, you could try our Balance Mineral Drink, which not only contains 5mcg of vitamin D, but also includes other essential nutrients such as magnesium, calcium and potassium! If you're after something stronger though, your local health food store should be able to help you out.

¹https://www.npr.org/sections/health-shots/2017/02/16/515428944/a-bit-more-vitamin-d-might-reduce-winter-colds-and-flu

²https://www.ncbi.nlm.nih.gov/pubmed/2717821

³https://www.medicinenet.com/vitamin_d_deficiency/article.htm#what_are_vitamin_d_deficiency_symptoms_and_signs_what_are_health_risks_of_vitamin_d_deficiency_continued

⁴https://articles.mercola.com/sites/articles/archive/2016/06/29/vitamin-d-insulin-resistance.aspx#_edn7

⁵https://www.vitamindcouncil.org/health-conditions/inflammatory-bowel-disease/

⁶https://www.gov.uk/government/news/phe-publishes-new-advice-on-vitamin-d

Low Vitamin D Symptoms Skin

Source: https://www.avogel.co.uk/health/skin/diet-and-lifestyle/can-vitamin-d-deficiency-affect-your-skin/

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Kidneys Produce Vitamin D

Kidneys Produce Vitamin D

Reader Question: I have a family history of cancer and have heard that lack of vitamin D might increase your risk. Should I take a supplement?

It can't hurt. An impressive (and growing) body of evidence supports a link between low vitamin D levels and an increased risk of developing colon cancer and breast cancer. One new study, published in the Archives of Internal Medicine, found that low levels of vitamin D were associated with an increased risk of death from any cause.

So how much D do you need? Unfortunately, we really don't know. The National Academy of Sciences currently recommends 200 IUs of vitamin D for people up to age 50 and 400–600 IUs for people older than that. (Note: These numbers include the vitamin D you get from food, and also the vitamin D your body manufactures when your skin is exposed to sunlight.) But some experts think that a higher amount (800–1,000 IUs) would offer additional health benefits. At the very least, I'd take a multivitamin that includes vitamin D. You should also ask your doctor to check your vitamin D level (it's a simple blood test) to find out where you stand. The American Medical Association is in the process of doing a comprehensive report on vitamin D, and when the results are available I'll be sure to share them with you.

I want to hear from you, so e-mail me your questions at dailywd@womansday.com.

Disclaimer: Your seeking information on health related topics and/or Sandra Adamson Fryhofer, MD's providing such information herein constitutes neither the solicitation of nor the provision of medical advice, services, care or treatment. Communication with Dr. Fryhofer on this website does not create a doctor/patient relationship. For concerns about your own particular medical condition, you should consult your own medical professional, who can examine and evaluate you. Communication on a website is not a substitute for taking an active role in your own medical care and treatment and being personally seen by a physician of choice in your area.

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io

Kidneys Produce Vitamin D

Source: https://www.womansday.com/life/a42199/vitamin-d-cancer-5535/

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Injectable Vitamin D Treatment

Injectable Vitamin D Treatment

Photo Courtesy: Michael Godek/Getty Images

Are you getting enough sun? In many parts of the world, that might prove difficult during the winter months — and it can impact more than your sunny disposition.When exposed to sunshine, our bodies produce vitamin D, something our bodies need to maintain healthy bones and teeth; support our immune and cardiovascular systems; and stave off certain diseases, like type 1 diabetes. Some reports suggest that roughly three-quarters of American teens and adults might not be getting enough vitamin D. So, how can you turn that number around?

The National Institutes of Health (NIH) makes recommendations for what one's daily intake of vitamin D should be based on age, gender and other factors. The recommendations, in micrograms (mcg), can be summarized as follows:

Photo Courtesy: Sean Gladwell/Getty Images

• Infants (up to 12 months): 10 mcg daily
• Children (1 to 13 years): 15 mcg daily
• Teens (14 to 18 years): 15 mcg daily
• Adults (19 to 50 years): 15 mcg daily
• Older adults (51 to 70 years): 15 mcg daily
• Seniors (70+ years): 20 mcg daily

So, how can you supplement your vitamin D intake if all that basking in the sun isn't cutting it? Thanks to the Dietary Guidelines for Americans, we've rounded up 10 healthy foods that can help you reach those daily vitamin D goals.

Salmon

Salmon comes in quite a few different varieties — canned sockeye salmon, smoked chinook salmon, canned pink salmon, cooked sockeye salmon, cooked pink salmon and even cooked wild coho salmon — and all of them are chock-full of vitamin D. All of these options will help you hit your goals. After all, a three-ounce serving of canned sockeye salmon contains 17.9 mcg of vitamin D, while a three-ounce portion of cooked sockeye salmon contains 11.1 mcg of vitamin D.

Photo Courtesy: Justin Ong/Getty Images

Smoked Whitefish

Want to change up that salmon intake? Whitefish can help with that. While whitefish are a species of fish, the term also refers to a cluster of types of fish, all of which have a mild, slightly sweet flavor. Some of the most popular "whitefish" include pollock, bass, cod, halibut, grouper and haddock. On average, a standard three-ounce serving of smoked whitefish contains an impressive 10.8 mcg of vitamin D.

Photo Courtesy: Bohemian Nomad Picturemakers/Getty Images

Swordfish

If you're looking for a terrific source of vitamin D, and to break up all that whitefish and salmon, try swordfish. These creatures can grow to be a whopping 1,400 pounds — and nearly 15-feet in length. While you wouldn't want to tangle with one of these in the ocean, encountering it as a nice, grilled steak is a treat. Best of all, a three-ounce portion will provide you with 14.1 mcg of vitamin D.

Photo Courtesy: Shawn Miller/Getty Images

Tilapia

Tilapia is a cluster of fish species that aren't found in nature. That is, tilapia is a farmed fish, which makes it pretty inexpensive. This mild species is the fourth most common type of seafood eaten by Americans, in part because of its versatility. We recommend a nice herb-and-parmesan crust, but, any way you slice it (or season it), a three-ounce portion will provide you with 3.1 mcg of vitamin D.

Photo Courtesy: Mike Kemp/Getty Images

Canned Tuna

Not into canned food? Well, canned fish should probably be your exception. In fact, canned tuna, in addition to being readily available and inexpensive, can make an abundance of tasty meals, from tuna salad and melts to casseroles. Best of all, a three-ounce serving of light tuna canned in oil contains about 5.7 mcg of vitamin D.

Photo Courtesy: LauriPatterson/Getty Images

Mushrooms

The five fish options we've listed above might not have surprised you, but this one might. Many varieties of mushrooms — including portabella, cremini, morels, chanterelles, maitake, and even your basic white button mushrooms — are excellent sources of vitamin D. In fact, half a cup of grilled portabella mushrooms delivers an impressive 7.9 mcg of vitamin D.

Photo Courtesy: Robert Lowdon/Getty Images

Eggs

Eggs — and, in particular, egg yolks — are one of the easiest, cheapest and quickest ways to nab some vitamin D. However, they may not be the food of choice for folks with high cholesterol. If your diet allows, whip up two scrambled eggs and enjoy getting 5% of your recommended daily intake of vitamin D first thing in the morning.

Photo Courtesy: valentinrussanov/Getty Images

Milk

Milk is more than just a great source of calcium. In fact, vitamin D is among its significant nutritional benefits. When it comes to a 16-ounce serving of cow's milk, the vitamin D content varies based on the milk's composition. For example, whole milk contains 6.3 mcg of vitamin D, while 2%, 1% and skim milk all contain 5.9 mcg. Even soy and dehydrated (powdered) milk will help you reach your goals by providing 5.8 mcg and 3.4 mcg of vitamin D respectively.

Photo Courtesy: JW LTD/Getty Images

Yogurt

Milk is not the only dairy product capable of delivering some serious vitamin D benefits. Of course, the nutritional value of yogurt changes depending upon the variety. For example, Greek-style yogurt contains more protein and less sugar than other types of yogurt. Nonetheless, you can still expect anywhere from 2 to 3 mcg of vitamin D per eight-ounce serving, regardless of the variety of yogurt.

Photo Courtesy: Westend61/Getty Images

Pork

So far, you've seen lots of fish and dairy options. You might be wondering, Where's the meat? Well, generally speaking, beef and chicken are not great sources of vitamin D. In fact, if you're a meat lover in search of some vitamin D, pork is your best bet. The nutritional value of pork varies depending upon the cut, method of preparation and more, but you're likely to find between 0.2 to 2.2 mcg of vitamin D in a standard three-ounce serving of pork.

Photo Courtesy: EasyBuy4u/Getty Images

Resource Links:

• The U.S. Department of Health and Human Services and Department of Agriculture's Dietary Guidelines for Americans
• The National Institutes of Health (NIH)

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Injectable Vitamin D Treatment

Source: https://www.symptomfind.com/health/vitamind-foods?utm_content=params%3Ao%3D740013%26ad%3DdirN%26qo%3DserpIndex

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How Much Vitamin D Should You Take In Alaska

How Much Vitamin D Should You Take In Alaska

The decline of traditional Alaska Native diets, which often include salmon, seal or whale, has contributed to a rise in Vitamin D deficiency. (Dan Young / National Park Service)

In Alaska, as in the rest of the circumpolar North, residents struggle with deficiencies of Vitamin D, a bone-strengthening nutrient the body absorbs from sunlight. The problem is especially serious for Alaska's indigenous children: From 2001 to 2010, Alaska Native children under the age of 10 had almost twice the national rate of rickets-associated hospitalizations.

Now Alaska health officials are recommending a big increase in Vitamin D supplements for children, infants and pregnant women.

The advisory comes after the Alaska Division of Public Health assembled its Alaska Vitamin D Workgroup, a panel made up of health care providers and other experts from Alaska, Canada and elsewhere. Details are in a bulletin report released by the division's epidemiology section.

For infants, the recommendation is for a doubling of the 400 International Units (IU) of Vitamin D usually advised — supplements of 800 IUs for breastfed babies and 400 IUs for babies drinking formula, most of which is already fortified with 400 IUs per serving. For pregnant women, the new recommendation is for an even bigger increase in Vitamin Ds — another 1,000 IUs through supplements or diet on top of the 400 already in prenatal vitamins. For children and adults up to 70 years of age, the recommended level is 600 IUs, consumed through diet, supplements or a combination, and for elders 70 and older, the recommended level is 800 IUs.

There are multiple reasons for Vitamin D deficiency in Alaska and elsewhere in the far north, especially for indigenous peoples: little or no winter daylight, darker skin pigments that inhibit absorption of the vitamin from sunlight, and a shift — especially among younger people — away from traditional Native diets with foods such as salmon, seal and whale. That dietary trend — and associated Vitamin D deficiency — extends to areas of the Arctic beyond Alaska. In Greenland, for example, one study of adults found lowest levels in the youngest age group. In Canada, there is a similar pattern among indigenous peoples, with less reliance on a traditional diet linked to lower Vitamin D levels.

One Canadian study found rates of rickets among children that even higher than the rate in Alaska, said Joe McLaughlin, Alaska's state epidemiologist and an author of the newly issued report. That study, which looked at data from 2002 to 2004, found a rate of 2.9 cases per 100,000 children, compared to Alaska's 2001-2010 rate of 2.23 per 100,000, he said. Incidents of rickets were most frequent among breastfed children in the far north, he said.

Alaska is not the first far-north jurisdiction to recommend boosted Vitamin D supplements, McLaughlin said. The Canadian Paediatric Society in 2007 developed its own guidelines for vitamin D supplementation, which included a recommendation of 800 IU a day for infants living above Latitude 55 in the winter months, meaning October to April, he said. The society is now considering an update that would recommend 800 IU year-round, he said.

The new Alaska Vitamin D recommendations are not mandatory, McLaughlin pointed out.

"These are recommendations for health care providers to consider; they are not requirements," he said in an email. "Clinicians should use their best judgment when determining whether or not to increase vitamin D supplementation for the infants and pregnant women they care for."

The Vitamin D workgroup is continuing to study the issue and may present more recommendations as information is gathered, the report said.

The full extent of Vitamin D deficiency in Alaska is not well understood.

"Because rickets is not a reportable condition in Alaska, it is difficult to ascertain statewide rates and characteristics of cases not identified in scientific studies," the report said. Additionally, there has been little study of rickets in non-Native children in Alaska, the report said. Much of the knowledge about Vitamin D deficiency comes from research done in Canada, it said.

Yereth Rosen is a 2018 Alicia Patterson Foundation fellow.

How Much Vitamin D Should You Take In Alaska

Source: https://www.arctictoday.com/alaska-health-officials-now-recommend-much-higher-vitamin-d-supplements/

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How Long To Give Breastfed Baby Vitamin D

How Long To Give Breastfed Baby Vitamin D

Vitamin D is needed to support healthy bone development and to prevent rickets, a condition that causes weak or deformed bones. Vitamin D deficiency rickets among breastfed infants is rare, but it can occur if an infant does not receive additional vitamin D from foods, a vitamin D supplement, or adequate exposure to sunlight.

Do infants get enough vitamin D from breast milk?

Breast milk alone does not provide infants with an adequate amount of vitamin D. Shortly after birth, most infants will need an additional source of vitamin D.

To avoid developing a vitamin D deficiency, the Dietary Guidelines for Americans and American Academy of Pediatrics recommend breastfed and partially breastfed infants be supplemented with 400 IU per day of vitamin D beginning in the first few days of life. Families who do not wish to provide a supplement directly to their infant should discuss with a healthcare provider the risks and benefits of maternal high dose supplementation options.

Once a child has started eating solid foods, parents can make sure their child is getting enough vitamin D from foods or supplements.

Why are infants at risk for vitamin D deficiency?

The risk for vitamin D deficiency is increased when there is limited exposure to sunlight or when an infant is not consuming an adequate amount of vitamin D. Although reducing sun exposure is important for preventing cancer, it also decreases the amount of vitamin D that a person can make from sunlight.

Other factors that decrease the amount of vitamin D a person can make from sunlight include:

• Living at high latitudes (closer to the polar regions), particularly during winter months.
• High levels of air pollution.
• Dense cloud covering.
• The degree to which clothing covers the skin.
• Use of sunscreen.
• Darker skin types.

How Long To Give Breastfed Baby Vitamin D

Source: https://www.cdc.gov/breastfeeding/breastfeeding-special-circumstances/diet-and-micronutrients/vitamin-d.html/

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Grow Light Vitamin D

Grow Light Vitamin D

Photodermatol Photoimmunol Photomed. Author manuscript; available in PMC 2010 Mar 27.

Published in final edited form as:

PMCID: PMC2846322

NIHMSID: NIHMS187186

Treatment of vitamin D deficiency with UV light in patients with malabsorption syndromes: a case series

Prakash Chandra

¹Graduate Program in Nutrition and Health Sciences and Department of Medicine, Atlanta, GA, USA

Linda L. Wolfenden

¹Graduate Program in Nutrition and Health Sciences and Department of Medicine, Atlanta, GA, USA

²Emory Cystic Fibrosis Center, Emory University School of Medicine, Atlanta, GA, USA

Thomas R. Ziegler

¹Graduate Program in Nutrition and Health Sciences and Department of Medicine, Atlanta, GA, USA

Junqiang Tian

¹Graduate Program in Nutrition and Health Sciences and Department of Medicine, Atlanta, GA, USA

Menghua Luo

¹Graduate Program in Nutrition and Health Sciences and Department of Medicine, Atlanta, GA, USA

Arlene A. Stecenko

²Emory Cystic Fibrosis Center, Emory University School of Medicine, Atlanta, GA, USA

Tai C. Chen

³Vitamin D, Skin & Bone Research Laboratory, Department of Medicine, Boston University School of Medicine, Boston, MA, USA

Michael F. Holick

³Vitamin D, Skin & Bone Research Laboratory, Department of Medicine, Boston University School of Medicine, Boston, MA, USA

Vin Tangpricha

¹Graduate Program in Nutrition and Health Sciences and Department of Medicine, Atlanta, GA, USA

See other articles in PMC that cite the published article.

Abstract

Background

Cystic fibrosis (CF) and short bowel syndrome (SBS) patients are unable to absorb vitamin D from the diet and thus are frequently found to be severely vitamin D deficient. We evaluated whether a commercial portable ultraviolet (UV) indoor tanning lamp that has a spectral output that mimics natural sunlight could raise circulating 25-hydroxyvitamin D [25(OH)D] levels in subjects with CF and SBS.

Methods

In initial pilot studies, two SBS subjects came to the outpatient clinic twice weekly for 8 weeks for UV light sessions of 6 min each. In a follow-up study, five CF subjects exposed their lower backs in a seated position to the sunlamp at a distance of 14 cm for 5–10 min depending on the skin type five times a week for 8 weeks. Blood samples for 25(OH)D and parathyroid hormone (PTH) measurements were performed at baseline and at the end of the study.

Results

In our study, with two SBS subjects, the indoor lamp increased or maintained circulating 25(OH)D levels during the winter months. We increased the UV lamp frequency and found an improved response in the CF patients. Serum 25(OH)D levels in CF subjects at baseline were 21 ± 3 ng/ml, which increased to 27 ± 4 ng/ml at the end of 8 weeks (P = 0.05). PTH concentration remained largely unchanged in both population groups.

Conclusion

A UV lamp that emits ultraviolet radiation similar to sunlight and thus produces vitamin D₃ in the skin is an excellent alternative for CF, and SBS patients who suffer from vitamin D deficiency due to fat malabsorption, especially during the winter months when natural sunlight is unable to produce vitamin D₃ in the skin. This UV lamp is widely available for commercial home use and could potentially be prescribed to patients with CF or SBS.

Keywords: cystic fibrosis, short bowel syndrome, tanning, ultraviolet radiation, vitamin D

Vitamin D is an important nutrient for intestinal calcium absorption for optimal skeletal health. Vitamin D can either be ingested from the diet (vitamin D₂ or D₃) or produced in the skin (D₃). Vitamin D (vitamin D₂ or D₃) absorption from the diet occurs primarily in the duodenum and jejunum (1, 2). Vitamin D₃ (cholecalciferol) is the form of vitamin D that can be produced endogenously in the skin following ultraviolet B (UVB) radiation (3). After production in the skin, vitamin D₃ is converted to the major circulating form of vitamin D, 25-hydroxyvitamin D₃ (25(OH)D₃). Circulating 25(OH)D₃ is then converted to 1,25-dihydroxyvitamin D₃ by the kidney 1-α-hydroxylase to act as a steroid hormone to increase the efficiency of calcium absorption primarily in the duodenum to maintain proper serum calcium levels for skeletal health and other cellular signaling processes (3).

Treatment of vitamin D deficiency in most healthy individuals is accomplished by giving vitamin D₂ (ergocalciferol) 50 000 IU once or twice a week for several weeks (4). However, patients with malabsorption as in short-bowel syndrome (SBS) and cystic fibrosis (CF) are not able to absorb vitamin D efficiently and thus have a high prevalence of vitamin D deficiency, leading to osteomalacia and osteoporosis. SBS patients have been given high-dose oral vitamin D supplementation without an improvement in vitamin D status due to poor intestinal absorption of vitamin D (1, 5, 6). CF patients have inefficient vitamin D absorption due to pancreatic exocrine insufficiency resulting in malabsorption of fat-soluble vitamins, including vitamin D. CF subjects absorb approximately 50% less vitamin D compared with what normal subjects absorb, depending on the degree of exocrine insufficiency (7). Current guidelines in CF patients to treat vitamin D deficiency with weekly high-dose ergocalciferol (vitamin D₂) have been ineffective (8–10). Despite 50 000 IU of ergocalciferol once a week for a total of 16 weeks in vitamin D-deficient CF patients, all of the patients remained vitamin D deficient (10).

Because patients with fat malabsorption syndromes cannot efficiently absorb vitamin D from the diet, an alternative method to raise vitamin D status, especially during the winter months where vitamin D cannot be made (11), would be by exposing the skin to UVB produced by a device to produce vitamin D₃ cutaneously (1, 12). Indoor tanning machines emit the same spectrum UVB radiation as sunlight (13). Studies evaluating indoor tanning beds have demonstrated that 25(OH)D levels can be raised after exposure to lamps that emit UVB (14). Cross-sectional studies have demonstrated that subjects who use an indoor tanning bed at least once a week have higher 25(OH)D levels than control subjects, which correlates with a higher bone mineral density (BMD) (13). Koutkia et al (1) successfully treated vitamin D deficiency, and associated musculoskeletal pains in a subject with SBS with the use of an indoor tanning bed.

In the current study, we sought to evaluate whether a commercially available portable desktop tanning machine could improve vitamin D status in patients with SBS and CF, disorders characterized by chronic malabsorption of fat-soluble vitamins.

Methods

Evaluation of a portable tanning machine to make vitamin D

To determine whether we could use a tanning device to improve vitamin D status in patients with malabsorption, we initially tested a commercially available desktop tanning machine to determine whether the UVB radiation emitted from the machine could convert 7-dehydrocholesterol (7-DHC) (pro-vitamin D₃), the compound naturally present in skin, to pre-vitamin D₃. We obtained the Sperti Del Sol portable tanning machine from KBD Inc. (Crescent Springs, KY, USA). The UVB output of this machine overlaps with the region of UVB necessary for vitamin D production in the skin (290–315 nm) (Fig. 1).

Ultraviolet spectrum output of the Sperti Del Sol sunlamp used in the study.

We exposed ampules containing a known quantity of 7-DHC to the machine at several distances and times to determine the quantity of pre-vitamin D conversion from 7-DHC. We determined the resultant amount of vitamin D₃ by standard high-performance liquid chromatography (HPLC) methods, as described by Holick et al. (15).

We determined that the portable tanning machine could effectively convert 7-DHC to pre-vitamin D₃ (Fig. 2). At several distances and times, from 0.5% to 5.0% of pre-vitamin D₃ could be detected in the ampules. Control ampules that had not been exposed to the tanning device did not demonstrate detectable pre-vitamin D₃. These data provided necessary preclinical data to proceed with our pilot study to evaluate the use of the portable tanning machine in CF and SBS patients with malabsorption. Based on these data, we developed a protocol to expose patients to UVB light via the tanning machine for up to 10 min at a distance of 14 inches.

Percentage of pre-vitamin D₃ formed after exposing ampules containing 7-dehydrocholesterol (7-DHC) to a portable tanning machine at several times and distances (◆, 14 inches; ■, 20 inches; ▲, 26 inches). Ampules containing 7-DHC (pro-vitamin D) were exposed to a portable tanning machine at several distances and times to determine the optimal conditions for vitamin D production in the skin. Vitamin D production was optimal at 14 cm from the device and an exposure time between 10 and 15 min.

Evaluation of a tanning machine to improve vitamin D status in two patients with severe SBS

Subjects

We obtained Emory University IRB approval to study the effect of the Sperti Del Sol sunlamp (Cresent Springs, KY, USA) in two SBS subjects with chronic, severe diarrhea and vitamin D insufficiency [25(OH)D <30 ng/ml], who both had failed oral courses of vitamin D therapy to improve vitamin D status. The first subject was a 49-year-old woman with 50 cm of the bowel remaining after massive small bowel and partial colonic resection secondary to mesenteric ischemia. The subject required parenteral nutrition (PN) solution 7 nights/week with 200 IU/day of vitamin D₃ to maintain nutritional status. Her left femoral neck bone density was 2.4 standard deviations below the peak density, and she had subjective pain and malaise. The second SBS subject was a 54-year-old woman who had multiple small bowel resections for a strangulated hernia in whom the distal duodenum was anastomosed to the right transverse colon. The subject also required PN solution 7 nights/week with 200 IU/day of vitamin D₃ to maintain nutritional status. Like the first subject, she suffered from severe night cramps and bone pains.

Study protocol in SBS patients

The study was conducted in the months from March to May. The two SBS subjects came to the outpatient clinic twice weekly for 8 weeks for the UV light sessions, which were administered by the study team. After baseline blood studies were obtained, both subjects started at an initial exposure time of 3 min from a distance of 14 inches to the exposed skin on the lower back in a seated position; the time was increased by 1 min to reach a target time of 6 min per UV light session in accordance with their skin type (Appendix A). The skin was inspected before and after each session to examine for any burns. Subjects gave a blood sample for 25(OH)D and parathyroid hormone (PTH) determinations every 4 weeks until the end of the study. Descriptive statistical analyses were performed in this pilot study in SBS patients.

Vitamin D status and PTH

Commercially available ELISA kits were used to measure 25(OH)D (IDS Ltd., Fountain Hills, AZ, USA), and intact PTH (Diagnostic Systems Laboratories, Webster, TX, USA) in blood samples at baseline and after 8 weeks of use of the tanning lamp.

Results

The first subject with SBS demonstrated a baseline serum 25(OH)D of 13 ng/ml that increased by 70% to 21 ng/ml at 4 weeks, and plateaued at this level after 8 weeks of UVB therapy. The serum PTH levels in this individual increased slightly from 150 to 165 pg/ml at the end of 8 weeks. There was a subjective reduction in the severity of her night cramps and bone pains. The second SBS subject demonstrated a baseline serum 25(OH)D of 17 ng/ml that increased by 40% to 24 ng/ml at 2 weeks, but then decreased to baseline levels (16 ng/ml) after 8 weeks of study. Her serum PTH levels decreased from 130 to 58 pg/ml at the end of 8 weeks.

Adverse events

Both subjects tolerated the monitored radiation sessions without any adverse events.

Evaluation of a tanning machine to improve vitamin D status during the winter months in subjects with CF Subjects

We obtained Emory University IRB approval to study the effect of the Sperti Del Sol sunlamp in CF patients with documented vitamin D insufficiency. The target population for the study was CF subjects cared for by the Emory Cystic Fibrosis Center (Atlanta, GA). Subjects were recruited by posted advertisements and referral by physicians. Subjects gave written informed consent for participation in the study. We included subjects older than 18 years of age who had documented vitamin D insufficiency [serum 25(OH)D <30 ng/ml] within the last three months, and had a history of gastrointestinal malabsorption documented by requirement of pancreatic enzyme replacement therapy or long-term PN therapy, or who had a skin sensitivity types II–VI (Appendix A). We excluded those subjects who had a history of photosensitivity, a history of active skin disease or any history of skin cancer, who were taking medications that limit sunlight exposure (such as tetracyclines or fluoroquinolones), who were taking more than 1000 IU vitamin D or vitamin D analogs daily orally, who had evidence of liver or kidney failure, who had fair skin type I (Appendix A), who were undergoing tanning sessions or subjects who were pregnant.

Study protocol

Based on the promising, but sub-optimal increase in serum 25(OH)D in these two pilot subjects with severe SBS, we increased the frequency of exposure to the tanning device to five times a week for the same time period of 8 weeks in the subsequent study in CF patients. The study period was from November to February. Subjects had a baseline 24-hour dietary recall and sunlight exposure questionnaire, and a baseline blood sample for the measurement of serum 25(OH)D and PTH. Subjects completed five UV light sessions per week for 8 weeks at home. Goggles for eye protection to be worn during the sessions were given. The target time per session was based on skin type (Appendix A). The subjects were asked to start with 3 min/session and to increase the time by 1 min/week till their target time. Subjects were instructed to expose the skin of the lower back to the tanning machine in a seated position from a distance of 14 in. Subjects came to the outpatient clinic every 2 weeks to for examination of the skin, and blood was drawn at 0 and 8 weeks for serum 25(OH)D and PTH mesurements.

Dietary history

Twenty-four hours of food recall was recorded for the day just before the first visit to the clinic. The dietary questionnaire had food portions that were visually quantified and standardized for the subject quantification. ESHA's The Food Processor SQL Version 9.8 Software was used to analyze the dietary intake.

Vitamin D status and PTH

We used the same commercially available ELISA kits that were used to measure 25(OH)D and intact PTH as in our pilot study of SBS subjects.

Statistical analysis

The results were represented as means ± SEM. The data were analyzed using Microsoft Excel (Office 2000), and Sigma Stat Version 3.0. Differences in the concentrations of serum total 25(OH)D were evaluated using a two-way paired t-test. Intention to treat was used in data analysis.

Results

Subject demographics

A total of eight CF subjects enrolled in the study. Two subjects who failed to report for the second tanning session were excluded. One subject was excluded due to non-compliance of the study protocol. Thus, five CF subjects were included in our analysis (Table 1).

Table 1

Baseline demographics of cystic fibrosis subjects who underwent UV light therapy five times a week for 8 weeks to improve vitamin D status

	N = 5
Age (years)	29.5 ± 3.4
Sex (M/F)	2/3
FEV (% of predicted) at 0 weeks	52 ± 13
FEV (% of predicted) at 8 weeks	50 ± 14
Weight (kg)	54.6 ± 2.4
Height (cm)	166 ± 3
Vitamin D supplementation (pills/day)*	1.0 ± 0.7
Dietary Vitamin D intake (IU/day)	237 ± 17
Sunlight exposure (min/week)	250 ± 68

Dietary vitamin D intake and supplementation

The mean dietary vitamin D intake averaged 237 IU/day. Three subjects were taking vitamin D supplements containing 400 IU of vitamin D daily, one subject was taking supplements containing 800 IU of vitamin D daily and the last subject was not taking any vitamin D supplementation.

Vitamin D status and PTH concentrations

Serum 25(OH)D levels in the five CF subjects at baseline were 21 ± 3 ng/ml, which increased to 27 ± 4 ng/ml at the end of 8 weeks (P = 0.05) (Fig. 3). Four out of five CF subjects had moderate to severe vitamin D deficiency [25(OH)D <20 ng/ml] at the start of the study, while only one out of five was so at the end of 8 weeks. The PTH concentrations remained unchanged during the 8-weeks study period (45 ± 10–43 ± 12 pg/ml).

Mean (± SEM) serum 25-hydroxyvitamin D concentration (ng/mL) before and after 8 weeks of UV light to cystic fibrosis (CF) subjects. Serum 25-hydroxyvitamin D [25(OH)D] levels in the five CF subjects at baseline were 21 ± 3 ng/ml, which increased to 27 ± 4 ng/ml at the end of 8 weeks (P = 0.05).

Adverse events

Mild transient erythema occurring after the use of the tanning device was reported by all subjects, but no sunburn or discomfort was reported.

Discussion

This pilot study demonstrates that a portable tanning device emitting UVB could maintain or improve vitamin D status in patients with CF or SBS during the winter months. Studies in SBS patients helped to define the UVB dose chosen for the CF study. In CF subjects, all were vitamin D deficient, despite taking regular vitamin D supplementation, due to malabsorption. During the winter, 8 weeks of the Sperti sunlamp resulted in a 25% increase in serum 25(OH)D concentration, and the prevalence of severe vitamin D deficiency [defined as 25(OH)D <20 ng/ml] decreased from 60% to 20%. All subjects demonstrated an increase in serum 25(OH)D concentrations, which achieved statistical significance. Similar results were found in the early pilot study in two SBS subjects. The use of a desktop tanning unit was well tolerated and no significant adverse events were reported by either group.

Sunlight, in particular UVB between the wavelengths of 290 and 315 nm, is the main source for producing vitamin D in the skin and is the primary source of vitamin D for the body. It is estimated that 90% of the daily body requirements are met by sunlight exposure (16, 17). One minimal erythemal dose (MED) of UVB exposure to 6% of the body surface area is equivalent to the ingestion of 600–1000 IU of vitamin D (18). Thus, exposure of the hands, face and arms two to three times a week is sufficient to meet the daily body vitamin D requirements in most individuals during the spring, summer and fall (18). Owing to the zenith angle of the sun during the winter months, very little UVB penetrates the earth above 351 latitudes, and thus sunlight exposure at this time will not result in sufficient vitamin D production (19, 20). For example, a third of healthy adults living in Boston were demonstrated to be vitamin D deficient at the end of winter (21).

In areas where there is limited sunlight or in situations where patients cannot absorb vitamin D from the diet, phototherapy using UV light has been used to correct vitamin D deficiency. In the early 20th century, mercury arc lamps were used to treat children with rickets in Russia. Indoor beds or tanning devices have been reported to be an effective alternative method to maintain or raise vitamin D status especially during the winter months in individuals with malabsorption (1, 22). Subjects who use an indoor tanning bed at least once a week have 150% higher 25(OH)D levels at the end of winter and higher BMD than matched healthy controls (13). Several other studies have used UVB from artificial sources in raising body vitamin D status (23–28).

Vitamin D insufficiency and metabolic bone disease remains a major health problem in patients with CF. The cause for decreased bone density in CF is multifactorial; however, due to the inability to absorb fat soluble vitamins, vitamin D insufficiency is a major contributing factor (8). Serum 25(OH)D in CF patients is positively correlated with BMD (29). A recent Johns Hopkins Hospital study found 109 out of 134 CF adults in the clinic to be vitamin D deficient [serum 25(OH)D <30 ng/ml], and none of the 33 CF subjects who finished 1 200 000 IU of oral vitamin D₂ over 4 months showed correction in their vitamin D status (10). The CF consensus guidelines for bone health suggest the use of UV lamps in subjects who fail to achieve optimal vitamin D status; however, no standard protocols have been established (8). A recent case–control study from Sweden demonstrated that CF subjects exposed to UV lamps one to three times weekly for 6 months showed an increase in circulating 25(OH)D from 20 to 50 ng/ml (27).

One of the weaknesses of our study is that we did not have randomized control subjects during the same months. Our small sample size also limits the power of our data analysis; however, the study subjects were exposed to the tanning light for just 8 weeks, which significantly increased their serum vitamin D levels by 25%. However, the values failed to reach the newly established levels to define vitamin D insufficiency [25(OH)D >32 ng/ml] (30). This suggests that the protocol may need to be extended for a longer time. Also, during this limited timeframe, we failed to show a significant decline in serum PTH concentration. Another limitation was that compliance could not be well assured in our second study with CF subjects because of the use of the tanning device at home.

In summary, we found that a portable tanning device used for tanning could be used to improve vitamin D status in selected individuals with intestinal malabsorption of vitamin D. Eight weeks of exposure to the sunlamp increased circulating 25(OH)D levels by 25% and reduced the prevalence of severe vitamin D deficiency. Further research is needed to determine the optimal duration of UVB exposure and to determine the long-term benefits of correcting vitamin D status by UVB on musculoskeletal health in these at-risk patients.

Acknowledgements

The authors acknowledge the assistance from the staff of the Emory University Cystic Fibrosis Center, Margaret Jenkins, Sandra Huff and Carrie Cutchins. The authors also acknowledge the technical assistance from James Shepherd in the operation of the Sperti Del Sol machine.

Appendix A

Skin sensitivity types to UVB radiation, and the recommended target tanning time sessions

Skin type scale*	Target (min/session)
Type I: Always burns easily, never tans	–
Type II: Always burns easily, tans minimally	3
Type III: Burns moderately, tans gradually	6
Type IV: Burns minimally, always tans well	9
Type V: Rarely burns, tans profusely	12
Type VI : Never burns, deeply pigmented	15

Footnotes

Conflicts of interest

Dr. Tangpricha and Dr. Holick received grant support from the Ultraviolet (UV) Light Foundation. The remaining authors report no conflicts of interest.

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Grow Light Vitamin D

Source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2846322/

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