Medical experts now claim that taking vitamin D supplements during early childhood may dramatically cut the odds of developing Type 1 diabetes later in life. Researches found that children given additional vitamin D were up to 80% less likely to develop Type 1 diabetes than those not given the supplement.

They also found that the higher and more regular the dose, the lower the likelihood of developing the condition. These findings came from the analysis of five studies in various countries.

One of the studies that was looked at was a Finnish sudy that followed more than 12,000 children born in 1966 in Finland. Their study showed that those who took any amount of vitamin D had a lower rate of diabetes than those who did, and those who took recommended amounts of vitamin D were at an 80% reduced risk of developing it.

Type 1 diabetes is an auto-immune disease in which the immune system destroys its own cells. It develops when insulin-secreting cells in the pancreas are destroyed.

Researchers believe that vitamin D, which is believed to be an immuno-suppressant agent, may prevent an overly aggressive response from the immune system. Nutrition experts recommend 8.5 microgrammes a day, and 7 microgrammes a day for those age 7 months to three years.

April 11th 2008, Lysaker, Norway - An increased intake of vitamin K2 may reduce the risk of prostate cancer by 35 per cent, suggest results from the European Prospective Investigation into Cancer and Nutrition (EPIC).

The findings, based on dietary intake from 11,319 men taking part in the EPIC Heidelberg cohort, are published in this month’s issue of the American Journal of Clinical Nutrition.

The study, by Katharina Nimptsch, Sabine Rohrmann and Jakob Linseisen, adds to a growing body of science supporting the potential health benefits of vitamin K2, most notable for bone and blood health.

In this recent study, dietary intake of vitamin K2 was linked to an inverse association with prostate cancer, while vitamin K1 intake did not offer any prostate benefits, report the researchers from the German Cancer Research Centre in Heidelberg.

Dr. Anne Bjørnebye Vik, Vice President R&D for NattoPharma, says: “ The potential anti-tumor effect of vitamin K2, in this case specifically prostate cancer, adds to the great potential for NattoPharma’s natural vitamin K2, MenaQ7™, one of the more documented derivatives in the group of vitamin K2’s or the so called long-chain menaquinones. As this interesting field of nutrition and cancer now also include vitamin K2, we are excited that NattoPharma’s natural menaquione-7, branded as MenaQ7™, shows to be the optimal form of vitamin K2.”

The study has also been welcomed by leading vitamin K researcher Cees Vermeer, PhD, from the VitaK and Cardiovascular Research Institute CARIM at the University of Maastricht. Commenting on the research, Dr. Vermeer says: “the beneficial effect of the long-chain menaquinones has previously been reported for cardiovascular disease; this specific form of vitamin K2 is characterized by preferential transport (via LDL) to extra-hepatic tissues (such as prostate and arterial vessel wall), and by very long half-life times (three days versus 1.5 hours) as compared to vitamin K1 and the short-chain menaquinone-4.

“I am highly pleased by this paper, which underpins the (widely underestimated) importance of long chain menaquinones for disease prevention,” Dr. Vermeer says.

“It also supports my opinion that intake of vitamin K2 supplements may have a significant contribution to public health.”

Study details

Nimptsch, Rohrmann and Linseisen from the Division of Cancer Epidemiology at the German Cancer Research Centre state that epidemiologic studies of dietary vitamin K intakes have not been conducted in relation to prostate cancer risk.

According to the European School of Oncology, over half a million new cases of prostate cancer are diagnosed every year worldwide, and the cancer is the direct cause of over 200,000 deaths. More worryingly, the incidence of the disease is increasing with a rise of 1.7 per cent over 15 years.

A food frequency questionnaire was used to assess habitual dietary intakes at the start of the study, with vitamin K intakes divided into phylloquinone (vitamin K1) and menaquinones (vitamin K2) and total and advanced prostate cancer in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition.

The researchers documented 268 incident cases of prostate cancer during the 8.6 years of follow-up. Of these, 113 cases were classified as advanced prostate cancer. While no reduction in the risk of prostate cancer was observed for vitamin K1 (phylloquinone), an increased intake of all menaquinones (vitamin K2) was associated with a 35 per cent reduction in risk. However, the researchers stated that this association was “non-significant”.

Furthermore, a strong association was documented when they considered only advanced prostate cancer, with increased intake of menaquinones linked to a 63 per cent reduction in risk.

While dietary sources of menaquinones include meat and fermented food products like cheese, and natto, Nimptsch and co-workers report that menaquinones from dairy had a stronger inverse association with advanced prostate cancer than did menaquinones from meat.

“Our results suggest an inverse association between the intake of menaquinones, but not that of phylloquinone, and prostate cancer,” concluded the researchers. “Further studies of dietary vitamin K and prostate cancer are warranted.”

Source: American Journal of Clinical Nutrition
April 2008, Volume 87, Number 4, Pages 985-992
“Dietary intake of vitamin K and risk of prostate cancer in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg)”
Authors: K. Nimptsch, S. Rohrmann, J. Linseisen
NattoPharma, Norway offers a natural vitamin K2 under the trade name MenaQ7.

K definitions

There are two main forms of vitamin K: phylloquinone, also known as phytonadione, (vitamin K1) and menaquinones (vitamins K2). K1 is found in green leafy vegetables such as lettuce, broccoli and spinach, and makes up about 90 per cent of the vitamin K in a typical Western diet; while K2, which makes up about 10 per cent of Western vitamin K consumption, is found mainly in fermented dairy products as e.g. cheese. The Japanese food Natto (fermented soybeans) is especially rich in vitamin K2.

A synthetic form of vitamin K, known as K3, does exist but is not recommended for human consumption.

The vitamin K’s are less well known than vitamins A to E, but this increasing body of research, as well as increased marketing and advertising from supplement makers, is raising public awareness of vitamin K.

ATLANTA, April 14 (UPI) — U.S. researchers say they are learning how vitamins and minerals can stimulate or prevent the development of colon cancer.

Emory University researchers in Atlanta find in a study of 92 patients that supplementing a diet with calcium and vitamin D appears to increase the levels of a protein call Bax — which controls programmed cell death — that may push pre-cancerous cells to self-destruct.

In another, 200-patient, case-control study, led by Dr. Robert Bostick of Emory University, high levels of calcium and vitamin D together are associated with increased levels of E-cadherin, which moderates colon cells‘ movement and proliferation.

A third study on the same 200-patients shows high levels of iron in the diet are linked to low levels of APC, a protein whose absence in colon cancer cells leads to their runaway growth.

All three studies — scheduled to be presented at the American Association for Cancer Research meeting in San Diego — use colorectal biopsy samples and are part of a larger effort to identify a portfolio of measurements which taken together could predict the risk of colon cancer.

“We want to have the equivalent of measuring cholesterol or high blood pressure, but for colon cancer instead of heart disease,” Bostick says in a statement.

an independent body that advises the Food Standards Agency on matters relating to new foodstuffs and processes.
Abbreviation ACNFP

a statutory committee that provides advice to the government on matters of food safety. Abbreviation

To help keep tired players from putting their controllers down, Japanese game peripheral maker Cybergadget has released a new line of vitamin supplements aimed at gamers.

“Game Sapuri” promises to keep gamers at their best, and is available in two flavors: Blue Berry, which aims to keep players refreshed after epic play sessions, and DHA, which boosts concentration while playing. Packs sell for 880 yen (about $9), and includes enough for 15 days of use (you take two a day).

Since Metal Gear Solid 3: Snake Eater included Japan’s favorite energy bar CalorieMate, one must wonder if  the upcoming Metal Gear Solid 4: Guns of the Patriots could see Snake take his daily dose of vitamins.

ATLANTA, April 14 (UPI) — U.S. researchers say they are learning how vitamins and minerals can stimulate or prevent the development of colon cancer.Emory University researchers in Atlanta find in a study of 92 patients that supplementing a diet with calcium and vitamin D appears to increase the levels of a protein call Bax — which controls programmed cell death — that may push pre-cancerous cells to self-destruct.

In another, 200-patient, case-control study, led by Dr. Robert Bostick of Emory University, high levels of calcium and vitamin D together are associated with increased levels of E-cadherin, which moderates colon cells‘ movement and proliferation.

A third study on the same 200-patients shows high levels of iron in the diet are linked to low levels of APC, a protein whose absence in colon cancer cells leads to their runaway growth.

All three studies — scheduled to be presented at the American Association for Cancer Research meeting in San Diego — use colorectal biopsy samples and are part of a larger effort to identify a portfolio of measurements which taken together could predict the risk of colon cancer.

“We want to have the equivalent of measuring cholesterol or high blood pressure, but for colon cancer instead of heart disease,” Bostick says in a statement.

Researchers at Emory University are learning how vitamins and minerals in the diet can stimulate or prevent the appearance of colon cancer.

Emory investigators will present their findings on biological markers that could influence colon cancer risk in three abstracts at the American Association for Cancer Research meeting in San Diego.

In a clinical study of 92 patients, supplementing diet with calcium and vitamin D appeared to increase the levels of a protein called Bax that controls programmed cell death in the colon. More Bax might be pushing pre-cancerous cells into programmed cell death, says Emory researcher Veronika Fedirko, who will present her team’s results (abstract 464).

Previous studies have shown that calcium and vitamin D tend to reduce colon cancer risk.

“We were pleased that the effects of calcium and vitamin D were visible enough in this small study to be significant and reportable,” Fedirko says. “We will have to fully evaluate each marker’s strength as we accumulate more data.”

The studies of colorectal biopsy samples are part of a larger effort to identify a portfolio of measurements that together can gauge someone’s risk of getting colon cancer, says Roberd Bostick, MD, MPH, professor of epidemiology at Emory’s Rollins School of Public Health.

“We want to have the equivalent of measuring cholesterol or high blood pressure, but for colon cancer instead of heart disease,” Bostick says. “These measurements will describe the climate of risk in the colon rather than spotting individual tumors or cells that may become tumors.”

More about Bostick’s plans for developing non-invasive blood or urine tests for colon cancer risk is available in an Emory Health Sciences Magazine article: http://whsc.emory.edu/_pubs/hsc/winter08/pdf/hold_out_your_finger.pdf

Another abstract from Bostick and his colleagues (565) demonstrates in a 200-patient case-control study that high levels of calcium and vitamin D together are associated with increased levels of E-cadherin, which moderates colon cells‘ movement and proliferation.

A third abstract on the same case-control study (5504) shows that high levels of iron in the diet are linked to low levels of APC, a protein whose absence in colon cancer cells leads to their runaway growth.

Bostick and his colleagues are participating in a ten-year multi-center study of the effects of increased vitamin D and calcium and biomarker-guided treatment of colon cancer recurrence. The study involves almost 2,500 people nationwide who have regular colonoscopies.

Thanks to sun avoidance and indoor lifestyles, Americans are vitamin D deficient. One of the worst things Americans have done to their health is avoid sun exposure. Most of us work inside then sit in our cars, and when we’re outside we slather ourselves with sun block and wear wide-brim hats and long sleeves. As a result, the majority of Americans have a serious vitamin D deficiency. It’s important to know whether your vitamin D levels are low, because a deficiency can increase the risk of our most common diseases, including heart disease and cancer.

In addition to its role in enabling calcium to be absorbed from the gut, new research is showing that vitamin D prevents heart disease, and stops the out-of-control cell growth that characterizes cancer. A number of population studies are suggesting that the less sunshine we get, the higher our risk is for cancers of the colon, prostate, breast, lung and, believe it or not, skin. Other research shows that vitamin D deficiency may be causing autoimmune diseases such as fibromyalgia and multiple sclerosis (MS). Research published in the British Medical Journal (vol. 237, p.316) on multiple sclerosis suggests that children who are exposed to the sun an average of two to three hours a day in the summer are a third less likely to develop MS. Vitamin D deficiency can also cause muscle weakness, osteoporosis and chronic low back pain.

The Sunshine Vitamin

Vitamin D is called the sunshine vitamin. When the sun’s ultraviolet rays are absorbed by the skin, a biochemical process begins in which an active form of vitamin D is created, enters the blood stream and then the cells. You can also get vitamin D from foods such as oily fish, dairy products and supplements, but sunshine is by far our most important source of this essential vitamin.

But haven’t we been warned away from sun exposure? Won’t it cause cancer and wrinkles? Well, yes and no. Our national hysteria about sun damage is grossly exaggerated. It’s one of those myths that has been repeated so much that most everyone assumes it to be true. The sunscreen industry has done a great job selling its wares by scaring us about sun exposure. However, if you dig down and do some research it’s a different story.

Yes, if you repeatedly get sunburned you somewhat increase your risk of non-melanoma skin cancer and wrinkles. The fairer the skin, the more easily it is sunburned and damaged. By far the biggest risk for skin cancer is simply having fair skin - with or without sunscreen. There’s really no substantial evidence that using sunscreen protects you from skin cancer. There is a weak association between melanoma and sunburn, but there is no evidence that using sunscreen prevents melanoma. There is some research indicating that exposure to the sun as a child reduces the risk of melanoma.

How Much Sun Do We Need?

According to Michael Holick, a vitamin D researcher and author of the book, The UV Advantage, between 11 a.m. and 2 p.m. in the summer (when the sun is most intense), a Caucasian with medium-fair skin living in Boston needs five to eight minutes of sunshine daily without sunblock. In winter you need more sun. People who live further north and/or have darker skin need more time and conversely, people who live closer to the equator and have fairer skin need less time.

There is considerable controversy about whether the process of skin tanning is beneficial and protective against the sun’s harmful rays, or whether tanning is actually a symptom of skin damage. Although repeated sunburns are correlated with later skin cancers, people who are brown from spending their lives working outside in the sun do not have higher rates of skin cancer: factors such as light skin, freckles, numerous moles, genetics and exposure to radiation and arsenic are greater risk factors.

The bottom line on healthy sunning is to avoid sunburn; in fact, you should be out of the sun long before your skin starts turning red. If you’re pale as a ghost, begin with just a few minutes a day and gradually work up. If you’re worried about facial wrinkles, wear a hat to shield your face, but allow at least your arms, legs and some of your chest to be exposed.

For those who have low vitamin D levels, live in colder, cloudier, northern climates or who just can’t get out in the sun enough, it’s wise to take a vitamin D supplement. The recommended daily allowance (RDA) of 400 IU is clearly too low. It was put in place before Americans became sun-phobic. Vitamin D is a fat soluble vitamin and as such can accumulate in the body and become toxic, so there has been justifiable concern about taking too much. Now that we have more research, it seems clear that we can safely take 2,000 IU daily in the D3 cholecalciferol form to maintain our vitamin D levels. If you are seriously deficient and your doctor wants to ratchet up your vitamin D levels quickly with large doses, be sure to test levels regularly. Some doctors will recommend 10,000 IU for a few months to get vitamin D levels back to normal.

What Is an Optimal Vitamin D Level?

Vitamin D levels below 20 ng/mL indicate a deficiency, while levels below 30 ng/mL are considered “low.” At this time, the scientific consensus is that optimal vitamin D levels are 30 to 60 ng/mL. Vitamin D can become toxic at levels greater than 150 ng/mL, which is why it’s important to test if you’re taking high dose supplements.

Who Is at Risk for Deficiency?

* The Elderly: As we age we absorb less vitamin D from the sun’s UV rays. Living in a nursing home or becoming homebound can limit exposure to sunshine. Muscle weakness and osteoporosis associated with vitamin D deficiency make the elderly more susceptible to falling and to fracture risk. Research indicates that vitamin D supplementation may decrease the risk of fractures.

* People with Dark Skin: The darker the skin is, the higher melanin levels are. Melanin blocks the action of sunlight on vitamin D precursors in the skin, requiring much longer sunlight exposure to generate adequate circulating vitamin D compared to people with fair skin.

* People with Limited Sunlight Exposure: People living at northern latitudes or who have limited sunlight exposure because of their working environment or cultural dress rules may have low vitamin D levels.

* People with Musculoskeletal Pain: People with symptoms of hypothyroidism, non-specific musculoskeletal pain, chronic low back pain, or fibromyalgia are frequently found to have low vitamin D levels and show clinical improvement after supplementation.

* Overweight or Obese People: Vitamin D can be locked up in fat stores in people who are overweight or obese. In clinical studies, obesity is associated with lower levels of circulating 25-hydroxy vitamin D.

New, Simple Vitamin D Test You Can Do at Home

Until recently, testing vitamin D levels involved a visit to the doctor, then a visit to a lab to draw blood, and considerable expense often not covered by health insurance. Thankfully there’s now a reasonably priced and simple-to-use blood spot test available to consumers that can be done at home.

What Is a Blood Spot Test?

A blood spot test involves a nearly painless finger stick and putting a few drops of blood on a small piece of special blotting paper.

Is the Blood Spot Test for Vitamin D Accurate?

It is highly accurate and unlike others, gives you a measure of both vitamin D2 and D3 and easy-to-interpret results.

To read more about vitamin D, find more references, and order a blood spot test, please visit the Virginia Hopkins Test Kits website ((http://www.virginiahopkinstestkits.com/…) .

References:

Berwick M, Armstrong BK et al, “Sun exposure and mortality from melanoma,” J Natl Cancer Inst 2005; 97:195–99.

Boscoe FP, Schymura MJ, “Solar ultraviolet-B exposure and cancer incidence and mortality in the United States, 1993-2002,” BMC Cancer 2006 Nov 10;6:264.

Dennis LK, Beane Freeman LE et al, “Sunscreen use and the risk for melanoma: a quantitative review,” Ann Intern Med
2003; 139: 966–78.

Ginanjar E, Sumariyono SS et al, “Vitamin d and autoimmune disease,” Acta Med Indones 2007 Oct-Dec;39(3):133-41.
Grant WB, “An estimate of premature cancer mortality in the U.S. due to inadequate doses of solar ultraviolet-B radiation,” Cancer 2002; 94:1867–75.

Holick MF, “Sunlight “D”ilemma: risk of skin cancer or bone disease and muscle weakness,” Lancet 2001; 357: 4–6.

Lin J, Manson JE et al, “Intakes of calcium and vitamin D and breast cancer risk in women,” Arch Intern Med 2007 May 28;167(10):1050-9.

Robien K, Cutler GJ et al, “Vitamin D intake and breast cancer risk in postmenopausal women: the Iowa Women’s Health Study,” Cancer Causes Control 2007 Sep;18(7):775-82.

Solomon CC, White E et al “Melanoma and lifetime UV radiation,” Cancer Causes Control 2004 Nov;15(9):893-902.

Thieden E, Philipsen PA et al, “Sunscreen use related to UV exposure, age, sex, and occupation based on personal dosimeter readings and sun-exposure behavior diaries,” Arch Dermatol 2005; 141:967–73.

About the author

Virginia Hopkins
Virginia Hopkins Health Watch
http://www.virginiahopkinshealthwatch.com

Vitamin C. Mmmm . . . maybe you think of a tall glass of Florida orange juice. Or maybe you grab it at the beginning of the cold season. But would you associate it with cardiovascular disease (CVD) or cancer? Maybe you should. According to an article published in October 2007, in the Journal of Nutrition, there is accumulating scientific evidence that very large (therapeutic) doses of vitamin C may be effective in treating both CVD and cancer. In addition, some scientists have hypothesized that the onset of these common degenerative diseases may actually be due to a vitamin C deficiency in the general population. Dr. Steven Hickey and Dr. Hilary Roberts with the Vitamin C Foundation and authors of the book ‘Ascorbate: the Science of Vitamin C’, have gone so far as to suggest that heart disease is actually a chronic form of the vitamin C deficiency disease called scurvy.

Vitamin C, found in a variety of fruits and vegetables, is essential not only for our good health, but our very survival. Without vitamin C, human beings will certainly die of scurvy, a disease characterized by bleeding gums, skin discolorations from small ruptured blood vessels, easy bruising, joint pain, loose and decaying teeth, and hyperkeratosis of hair follicles. But along the continuum of health, there is a difference between survival and optimal human health. The real question is how much vitamin C is required for optimal health?

Vitamin C has many essential roles in the body. It is required for the synthesis of collagen, which is a main structural protein in our bodies, giving support to our tissues, including strengthening our blood vessels, ligaments, tendons, bone, and teeth. It is also required for synthesis of hormones, neurotransmitters, and other important substances needed for metabolism. In addition to these functions, vitamin C is a powerful antioxidant. It neutralizes free radicals before they have a chance to damage our cells. Vitamin C is arguably one of the most important antioxidants in our human physiology for its versatility and wide ranging presence.

How Much?

The government’s Recommended Daily Allowance (RDA) is defined as the daily amount of a nutrient considered sufficient to meet the requirements of most healthy individuals. For Vitamin C, it is 75 mg/day for adult women and 90 mg/day for adult men (smokers are recommended to have an additional 35 mg/day). The current RDA is adequate to prevent death or serious health issues from acute deficiency of vitamin C (e.g., scurvy). The RDA is also adequate for required collagen and hormone synthesis (the RDA is mainly based on this). But to work effectively as an antioxidant, scientists are learning that vitamin C levels need to be significantly higher in our bodies. And the debate now is over how much is needed.

If we ate the recommended 5 servings of fruits and vegetables per day, we’d easily consume double the RDA for vitamin C and likely a lot more. According to Linus Pauling, a two time Nobel Prize winning chemist who is noted for his vitamin C research, our early human ancestors probably consumed 2,300 mg/day to 9,500 mg/day of vitamin C from their plant-based diet. This is 25 to 100 times more than today’s RDA for an adult man!

History

Scientists have determined that about 40,000 years ago humans lost their own ability, through a genetic mutation, to manufacture vitamin C. Our DNA no longer allowed our cells to make an enzyme which is required to produce vitamin C internally. Evolutionary biologists would argue that the mutation conferred a survival advantage. After all, humans could conserve energy by not manufacturing something that was already abundantly available in their diet.

Along the way, our dependence on fruits and vegetables became obvious. In the 1700’s, sailing ships started stocking limes or vegetables to prevent their crew members from dying of scurvy during long voyages. In 1928, Hungarian biochemist, Albert Szent-Györgyi, finally isolated the mysterious substance known as vitamin C. Since then, scientists have been working to understand exactly how vitamin C functions in our bodies.

Beyond Mere Survival

Today, scientific evidence is highlighting a discrepancy between the amount of vitamin C needed to avoid acute deficiency disease and the amount needed for effective antioxidant protection to ward off major degenerative diseases. This hypothesis is based on vitamin C’s function as a powerful, versatile and pervasive antioxidant in our bodies.

Free radicals are molecules with an unpaired electron that make them highly reactive. They “steal” an electron to make up a more stable pair, hence damaging the molecules around them that have had to relinquish an electron. Free radicals have shown to be a significant contributing factor in the development of cardiovascular disease (CVD) and cancer. They can trigger premature cell death and inflammation in our vascular system. They can reduce the availability of nitric oxide which helps maintain healthy artery dilation and blood flow. Free radicals can also oxidize LDL cholesterol. As we’re learning, it’s not so much the LDL cholesterol that’s implicated in the development of heart disease, it’s that the LDL cholesterol has been damaged, or “oxidized”, by free radicals. Free radicals can also cause DNA mutation and damage the supportive structure of our cells which can contribute to the development of cancer.

Many studies have shown that increased vitamin C intakes and increased plasma vitamin C concentrations are correlated with a decrease in degenerative diseases. Scientists have also determined and explained the specific mechanisms by which vitamin C scavenges and neutralizes these free radicals, thus providing powerful protection against free radical damage.

Conclusion

The current RDA may be sufficient to avoid acute deficiency disease but may not be enough to help protect us from free radical damage. A reduction of disease risk has been associated with 5 servings of fruits and vegetables per day, and this is likely due at least in part to their vitamin C content. But the vitamin C content in these servings is easily double the RDA. Scientists researching vitamin C have yet to agree upon how much is required for optimal human health. Their estimates vary and typically start at 400 mg/day and go higher.

Dr. Steve Hickey with the Vitamin C Foundation has published open letters to the Food and Nutrition Board and the National Institutes of Health, laying out the reasons why the current RDA is insufficient and why it should be reexamined and readjusted upward.

In the meantime, we can support our health and reduce our risk of degenerative diseases by making sure not to skimp on our 5 servings of fruits and vegetables per day. We may fortify ourselves with a good quality multi-vitamin supplement for the extra vitamin C it provides.

Vitamin C is a water-soluble vitamin, which means that it is not stored in the body and must be replaced by our diet every day. The Tolerable Upper Intake Level (UL) is the maximum continual intake of a nutrient that is unlikely to cause adverse health effects in almost all people, and for vitamin C the UL is 2 g/day (2,000 mg/day). The most common side effect of taking an amount larger than this is diarrhea. Therefore, healthy individuals have little concern of toxicity if consuming more vitamin C than specified by the RDA.

One word of caution - people who have a high risk of kidney disease, kidney stones, or disorders of iron metabolism should avoid large doses of vitamin C (>500mg). Consult your doctor or nutritionist prior to taking supplementation.

Virtually all fruits and vegetables contain some amount of vitamin C. According to the USDA nutrient database, fruits and vegetables that are among the highest in vitamin C content include: orange juice, grapefruit juice, peaches, peppers (sweet and hot), papayas, strawberries, broccoli, Brussels sprouts, kohlrabi, pineapple, and kiwi fruit. Other fruits noted for their high vitamin C content include: jujube, acerola, camu camu, guava, red and black currants, mango and persimmon.

About the author

Leigh Kirk is an investigative nutritionist currently pursuing her Master of Science in Human Nutrition at the University of Bridgeport. Special interests include disorders of metabolism, research on fats, antioxidants, trace minerals, and the ecology of nutrition. Email: investigativenutritionist@gmail.com