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Issue # 66.10 - A-Z of Nutrition

A to Z of Nutrition: Magnesium Quantitatively

Magnesium ranks next to phosphorus and calcium in the body. Magnesium is intimately involved with calcium in metabolism.

What does it do?

More than 65% of the magnesium content of the body is found in the bone, where along with calcium and phosphorus it provides structure and strength. The mineral plays a vital role in energy release, as it is a cofactor in energy-producing reactions. It is also needed in RNA synthesis and in DNA replication - i.e. in cell production. Additionally, magnesium is important in the functioning of nerves and muscles

What are the deficiency signs?

Possible manifestations of magnesium deficiency include muscle cramps and twitches, insomnia, irritability, rapid heartbeat, low blood sugar and anxiety.

Is it toxic?

There is no evidence to suggest that large intakes of magnesium are harmful to humans with normal kidney function. Excessive circulating levels of magnesium are almost impossible to achieve by ingestion from foods, but high levels induced by intravenous administration can interfere with nerve transmission and are therefore very dangerous. Carcinogenicity may occur at doses of 3000mg/kg body weight which amounts to 195g per day based on a 65kg human. 3-5g of magnesium salts have a purgative action and is harmful if taken frequently for this purpose.

Who should supplement?

Magnesium is often taken by women to ease PMT, especially stomach cramps and sugar cravings. The use of magnesium in this situation makes a lot of sense because tests have borne out that blood magnesium levels do drop before a period. Other conditions in which magnesium has been found to be helpful are involuntary muscle twitches (of the eyelid for example) and combined with calcium for muscle cramps. Again in relation to muscle function, it is also thought that magnesium has some protective effect on the heart, perhaps more particularly in the prevention of arrhythmias (irregular heart beats)

Intake levels

Milligrams (mg) RDA 300 Upper safe level

(long term)300

(short term) 400

Which foods?


Peanuts, roasted 180

Bread, wholemeal 76

Cheese, cheddar 25

Fish, white 23

Chicken 21

Potatoes 17

Oranges 13

Eggs 12

A to Z of Nutrition: Selenium

Now regarded as an essential trace element in humans and animals, selenium is found in uneven quantities in parts of the earth\'s surface. Selenium toxicity has been noted in areas where selenium content of the ground is high, but selenium deficiency is a far more widespread problem - contributing to infertility, heart problems, eye disease and premature ageing.

What does it do?

Selenium carries out its main functions as part of the enzyme glutathione peroxidase. Glutathione peroxidase is an antioxidant that protects intracellular structures against oxidative damage by free radicals.

Selenium is known to have a role in the following:

Preservation of normal liver function.

Antioxidant protection of all body cells.

Maintenance of a healthy heart.

Inhibition of harmful effects from heavy metals such as arsenic, cadmium, mercury and lead.

Production of beneficial anti-inflammatory prostaglandins.

Production of thyroxine hormone.

What are the deficiency signs?

Selenium deficiency has traditionally occurred in areas where the soil is particularly low in this mineral. However, as modern lifestyles have allowed us to eat foods from very many different countries of origin, true selenium deficiency has become less of a problem.

One selenium deficiency disease is known as Keshan\'s disease - after the province in China that has the lowest soil selenium levels in the world. Symptoms are mainly to do with the heart - specifically involving wastage of the heart muscle.

Another selenium deficiency disease is known as Kaschin-Beck disease, and affects the cartilage in the joints.

Is it toxic?

Evidence of disturbed selenium regulation occurs at intakes above 750?g and deterioration and loss of nails have been noted in adults ingesting 900?g per day

Who should supplement?

The groups of people particularly found to be at risk of selenium deficiency are as follows:


The elderly

Pregnant and nursing mothers


Rheumatoid arthritis sufferers

Intake levels

There is no EC Recommended Daily Allowance for selenium. Upper safe level 200 ?g

Which foods?


Organ meats 40

ish and shellfish 32

Meat 18

Wholegrains & cereals 12

Dairy products 5

Fruit and vegetables 2

A to Z of Nutrition: Zinc

The zinc content of the adult body is approximately 2-3g, and the mineral is found most highly concentrated in muscles, liver, kidneys and eyes. In males, zinc is also present in large amounts in the prostate gland and sperm. A component of over eighty enzymes, zinc functions in many reactions in the human body.

What does it do?

Zinc is necessary for normal cell division and function. It is found in alpha-macroglobulin, an important protein in the body\'s immune system and is needed for the functioning of the thymus gland. It is necessary for the growth in children and maturation of the sex organs at puberty. The mineral is also needed for the production of male sperm and female ova. Zinc helps clear certain toxic metals from the body (e.g. cadmium and lead). Zinc is also essential for the maintenance of vision, taste and smell; for the release of insulin and for the absorption and metabolism of vitamin A

What are the deficiency signs?

The deficiency signs of zinc are frequent infections, delayed wound healing, reduced appetite, decreased sense of taste or smell, skin disorders, and white marks on nails.

Is it toxic?

After acute ingestion of 2g or more of zinc, symptoms such as nausea, vomiting and fever develop. Long term intakes of around 75-300mg of zinc are associated with features of copper deficiency such as neutropenia (low levels of neutrophil type of white blood cell) and anaemia.

Who should supplement?

A supplement of zinc may be helpful in the following situations:

Those with skin conditions i.e. acne and eczema

Those with inflammation of the prostate

Those with slow wound healing

Those with high alcohol intake

For increased fertility

Intake levels:

milligrams (mg) RDA 15

Upper safe level (long term) 15

(short term) 50

Which foods?


Cheese Cheddar 4.0

Beef, stewing steak 3.8

Lentils 3.1

Bread, wholemeal 1.8

Eggs 1.5

Chicken 1.1

Bread, white 0.6

Fish, white 0.4

Milk 0.4

Potatoes, old 0.3

References 1. Vitamin and Mineral Safety, Council for Responsible Nutrition: 1997 2. Health Essentials, Vitamin Guide: 1994 3. Manual of Nutrition (MAFF):1989

Issue # 66.9 - Circulatory Health

Answer to Varicose Veins?

A varicose vein is a superficial vessel that is abnormally lengthened, twisted, or dilated, seen most often on the legs and thighs. Varicose veins develop spontaneously and are usually attributed to a hereditary weakness of the vein. The valves in the vein that keep the blood circulation upward toward the heart are usually incompetent. Increased pressure from long standing or exertion, or internal factors such as pregnancy, or lessened support by the tissues surrounding the veins that occur with ageing and obesity cause the weakened veins to dilate. Extracts of horse-chestnut seed standardised for aescin (a key component) appear to be as effective as compression stockings without the nuisance. For example, in a well-designed study, the effectiveness of horse chestnut seed extract versus leg compression stockings was examined in 240 patients with varicose veins. Patients received either horse chestnut seed extract (50mg of aescin a day), compressed stockings, or a placebo. Patients were treated over a period of twelve weeks. Effectiveness was evaluated by a machine that measures the volume of fluid in the leg. After the three week trial, lower leg volume of the more severely affected leg decreased an average of 56.5ml with compression therapy and 53.6 ml with horse chestnut seed extract while it increased by 9.8 ml with placebo. Compression stockings and horse chestnut seed extract produced nearly identical reductions in oedema. So why take the horse chestnut rather than wear the stockings? These are not regular stockings; they are made from special material, very expensive, and are quite difficult to put on, not to mention uncomfortable to wear. Horse chestnut seed extracts standardised for aescin exert anti-oedema and anti-inflammatory properties, and decrease capillary permeability by reducing the number and size of the small pores in the capillary walls. The reduction in capillary permeability and oedema appears to result from inhibition of the enzymes that break down the support structures of the vein.

Lancet. 1996 Feb 3;347(8997):292-4

Improvement in CVI related signs?

Conservative therapy of chronic venous insufficiency (CVI) consists largely of compression treatment. However, this often causes discomfort and has been associated with poor compliance. Therefore, oral drug treatment is an attractive alternative. The objectives of this trial were to review the evidence from rigorous clinical trials assessing the efficacy and safety of oral horse chestnut seed extract (HCSE) versus placebo, or other treatments for CVI. Overall, there appeared to be an improvement in CVI related signs and symptoms with HCSE compared with placebo. Leg pain was assessed in seven placebo-controlled trials. The evidence presented implies that HCSE is an efficacious and safe short-term treatment for CVI. However, several caveats exist and more rigorous RCTs are required to assess the efficacy of this treatment option.

Cochrane Database Syst Rev. 2004;2:CD003230

Issue # 66.8 - Joint Health

Efficacy of oral glucosamine sulfate and chondroitin sulfate?

To assess the structural and symptomatic efficacy of oral glucosamine sulfate and chondroitin sulfate in knee osteoarthritis through independent meta-analyses of their effects on joint space narrowing, Lequesne Index, Western Ontario MacMaster University Osteoarthritis Index (WOMAC), visual analog scale for pain, mobility, safety, and response to treatment. The results demonstrated a highly significant efficacy of glucosamine on all outcomes, including joint space narrowing and WOMAC. Chondroitin was found to be effective on Lequesne Index, visual analog scale pain, mobility, and responding status. Safety was excellent for both compounds. This study demonstrates the structural efficacy of glucosamine and indistinguishable symptomatic efficacies for both compounds.

Arch Intern Med. 2003 Jul 14;163(13):1514-22

Effective in ameliorating physical symptoms?

There is preliminary clinical evidence to support the contention that the anti-inflammatory and analgesic properties of bromelain help to reduce symptoms of osteo- and rheumatoid arthritis. However, there have been no controlled studies of its effects on joint health in healthy subjects who lack such diagnosis. The current study investigated the effects of bromelain on mild acute knee pain of less than 3 months duration in otherwise healthy adults. Bromelain was administered at levels of 200 mg or 400 mg per day. It concluded that bromelain may be effective in ameliorating physical symptoms and improving general well-being in otherwise healthy adults suffering from mild knee pain in a dose-dependant manner. Double blind, placebo-controlled studies are now warranted to confirm these results.

Phytomedicine. 2002 Dec;9(8):681-6

Issue # 66.7 - Pregnancy/Infant/Child Health

Effects of micronutrient supplementation on maternal biological status and newborn anthropometrics measurements

A recent study investigated the possible beneficial effects of a micronutrient supplementation to 65 apparently healthy pregnant women on maternal biological status and newborn physical characteristics, such as height and weight, by daily consuming a micronutrient supplement or placebo over the gestation period. The mothers\' plasma micronutrient levels and oxidative stress parameters were measured at 14 and 38 weeks of gestation and the newborn\'s anthropometric characteristics were measured at delivery. The results showed that in the supplemented group, folic acid, vitamin C, E, B2, B6 and beta-carotene levels were higher than in the placebo group. Birth weights were increased by 10% and the number of low newborn weights decreased significantly when the mother received supplementation. These results suggest that the use of combined micronutrient supplements improve babies and maternal biological status and emphasises that optimal micronutrient nutrition should be encouraged.

European Journal of Clinical Nutrition (2004) 58, 52-59

Reduce the risk of type 1 diabetes?

In Norway, cod liver oil is an important source of dietary vitamin D and the long-chain n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid, all of which have biological properties of potential relevance for the prevention of type 1 diabetes. The main objective was to investigate whether the use of dietary cod liver oil or other vitamin D supplements, either by the mother during pregnancy or by the child during the first year of life, is associated with a lower risk of type 1 diabetes among children. The results showed that the use of cod liver oil in the first year of life was associated with a significantly lower risk of type 1 diabetes. It concluded that cod liver oil may reduce the risk of type 1 diabetes, perhaps through the anti-inflammatory effects of long-chain n-3 fatty acids.

Am J Clin Nutr. 2003 Dec;78(6):1128-34.

Can oral magnesium reduce frequent migrainous headaches in children?

A study was carried out to assess whether oral magnesium can reduce migrainous headache frequency, severity, and associated features in children compared to placebo. They recruited children of ages 3 to 17 years who reported a 4-week history of moderate-to-severe headache with a throbbing or pulsatile quality, associated anorexia/nausea, vomiting, photophobia, or relief with sleep, but no fever or evidence of infection. They received either magnesium (9 mg/kg per day by mouth divided 3 times a day with food) or matching placebo for 16 weeks. Results showed a statistically significant decrease over time in headache frequency and severity in the magnesium group but not in the placebo group. This study shows that treatment with magnesium may lead to a significant reduction in migrainous headache days in children.

Headache.2003 Jun;43(6):601-10


Issue # 66.6 - Menopause Research

The effects of phytoestrogen isoflavones on bone density in women

Phytoestrogens are oestrogenic compounds found in plants that consist of isoflavones. Isoflavones are known for their estrogenic activity, which play an important role in skeletal homeostasis and prevention of bone loss from occurring. Ovarian hormone deficiency is one of the most important risk factors of osteoporosis and since isoflavones are structurally similar to mammalian oestrogens they may have potential bone-sparing properties. A study was conducted on 177 women aged 49-65 to determine the effect of red clover-derived isoflavone supplement on bone density. The supplement contained biochanin A, formononetin, genistein and daidzein and was taken for a year. Results showed that the loss of the lower spine bone and bone mineral density was significantly lower in the women taking the isoflavone supplement than in those taking the placebo.

Am J Clin Nutr 2004; 79:326-33

Is hormone Replacement Therapy Necessary?

Menopause marks a transitional phase in a woman\\\'s life when menstruation ceases. This change of life is the result of declining ovarian function due to the ageing of the ovaries. Menopause can be accompanied by deficient or excessive functioning of the glandular and autonomic nervous systems, giving rise to nervousness, hot flushes, excitability or depression, dizziness, headaches, sweating and other symptoms. Such disturbances are severe when cessation of ovarian function is relatively rapid. If symptoms are severe, they may be eased by hormone replacement therapy (HRT), utilising a combination of oestrogen and progesterone. The obvious question is: \\\"Is hormone replacement therapy necessary?\\\" Phytoeostrogens are plant compounds that mimic the action of oestrogen and therefore may be useful during the menopause. Isoflavones are the most highly investigated subgroup of phytoestrogens found in soy, flaxseed, nuts, whole grains, apples, fennel, celery, parsley, and alfalfa, but the best source is from red clover. The reason is because some people who are allergic to soy would not be able to use soy isoflavones, whereas red clover isoflavones are hypoallergenic. Phytoestrogens offer significant advantages over the use of oestrogens in the treatment of menopausal symptoms. While both synthetic and natural oestrogens may pose significant health risks, including increased risk of cancer, gallbladder disease, strokes and heart attacks, phytoestrogens have not been associated with these side effects. A recent study investigated the effectiveness of a red clover isoflavone supplement on the change in hot flush frequency in postmenopausal women. Thirty women experiencing more than five flushes per day were enrolled. They all received placebo tablets for 4 weeks and were randomised to either placebo or 80mg red clover derived isoflavones for a further 12 weeks. The efficacy was measured by the decrease in number of hot flushes per day. The results showed a 44% reduction in the isoflavone group whereas there was no reduction in the placebo group. Therefore this study demonstrates the effectiveness of red clover derived isoflavones in the management of hot flushes.

Maturitas 2002 Jul 25;42(3):187



Issue # 66.5 - Importance of Fruit and Veg

Are fruit and vegetable intakes predictors of bone size in early pubertal children?

Studies have shown that 92% of urinary calcium excretion reflects bone metabolism rather than dietary calcium intake. A study was carried out to determine whether consuming fruit and vegetables over 3 times a day was beneficial to bone mass in children. Results showed that children consuming greater than three servings of fruit and vegetables a day had more bone area of the whole body, radius and lower urinary calcium excretion than the children who reported consuming less than three servings of fruit and vegetables per day. This shows that high fruit and vegetable intakes have beneficial effects on the bone area and radius of the whole body in early pubertal girls. The lower urinary calcium output was associated with higher fruit and vegetable intakes. Am J Clin Nutr 2004:79;311-7 Isoflavones and woman\'s health There is evidence that diets which contain high levels of phytoestrogenic isoflavonoids are associated with a low incidence of osteoporosis and menopausal symptoms. Plant extracts such as red clover, which contain high levels of isoflavonoids, have been used to reduce menopausal symptoms and have been shown to reduce bone loss in healthy women. Research shows that these phytoestrogens do not cause any oestrogenic increase in breast density, which indicates that they are unlikely to cause an increased risk of breast cancer.

Breast Cancer Res. 2004;6(3):140-2

Can fruit and vegetable consumption lower LDL cholesterol?

An elevated LDL-cholesterol is a risk factor for coronary artery disease. In a current study they used data from 4466 adult participants of the National Heart, Lung, and Blood Institute Family Heart Study to evaluate whether higher intakes of fruit and vegetables is inversely related to LDL concentrations in men and women, independent of other risk factors. Results showed that fruit and vegetable consumption was inversely related to LDL in men and women, independent of age, smoking status, exercise, educational attainment. The average daily serving of fruit and vegetables was 3.2 for men and 3.5 for women. Subjects in the highest fruit and vegetable intake groups had LDL concentrations that were 6-7% lower than those in the lowest fruit and vegetable intake groups.

Am J Clin Nutr 2004;79:213-7

Issue # 66.4 - The Influence of Piperine and Curcumin

Does piperine increase bioavailablity?

A significant number of problems faced by people over the age of sixty may be attributable to nutritional deficiencies. Many elderly people have malabsorption problems, in which the nutrients in food are not properly absorbed by the gastrointestinal tract due to the decrease of the production of digestive enzymes. There are also many disorders that are associated with an inability to absorb nutrients successfully such as IBS, Crohn\'s disease and Ulcerative colitis. A lack of nutrients may lead to serious conditions which may be life threatening. So the question is \'What can naturally increase the bioavailability of nutrients?\' Piperine is a phytonutrient and is the active ingredient of black pepper. It is lipid soluble therefore alters the structure of the cell membranes, thereby increasing the permeability of the intestinal cell membranes which leads to better absorption of nutrients. It is regarded as a thermonutrient as it can stimulate thermogenesis. This means that it can increase energy available for nutrient absorption by increasing the activity of an enzyme which breaks down ATP. Piperine can also increase blood flow to the gastrointestinal tract and can also increase the levels of enzymes involved in transport of nutrients into intestinal cells. A study was designed to investigate the absorption dynamics of piperine in the intestine on oral absorption, using human intestinal cells as a model. The results suggested that piperine is easily absorbed across the intestinal barrier and it may increase the permeability of the intestinal cell membrane, thus helping efficient transport across the intestinal wall. Another study also demonstrated that piperine may have the ability to increase the bioavailablity of certain nutrients. This study used coenzyme Q10 as the nutrient and the results showed that piperine did increase plasma levels of coenzyme Q10 and it is thought that this bioenhancing mechanism is non-specific and possibly based on its description as a thermonutrient. The bioenhancing effects of piperine have been demonstrated in several other studies which show that piperine can improve the absorption of many nutrients. These include: Vitamin C, Selenium, Beta-carotene, Vitamin A, Vitamin B6, and Coenzyme Q10.

Indian J Exp Biol 1998 Jan;36(1):46-50

Mol Cell Biochem 1998 Dec; 189(1-2):113-8

Nahrung 2000 Feb; 44(1):42-6

Could piperine derived from black pepper increase the plasma levels of coenzyme Q10?

A study showed that supplementation of 120mg coenzyme Q10 with 5mg piperine for 21 days produced a statistically significant, approximately 30% greater levels of coenzyme Q10 in the plasma than was observed with placebo. It is postulated that the bioenhancing mechanism of piperine to increase plasma levels of supplemental Q10 is based on its thermonutrient nature.

0955-28632000 Feb 1;11(2):109-113

Inhibits the growth of H. pylori?

Curcumin, a polyphenolic chemical constituent derived from turmeric (Curcuma longa), has been shown to prevent gastric and colon cancers in rodents. Many mechanisms have been proposed for the chemopreventative effects, although the effect of curcumin on the growth of Helicobacter pylori has not been reported. H. pylori is a Group 1 carcinogen and is associated with the development of gastric and colon cancer. A methanol extract of the dried powdered turmeric rhizome and curcumin were tested against 19 strains of H. pylori. Both the methanol extract and curcumin inhibited the growth of all strains of H. pylori in vitro with a minimum inhibitory concentration range of 6.25-50 micrograms/ml. These data demonstrate that curcumin inhibits the growth of H. pylori strains in vitro, and this may be one of the mechanisms by which curcumin exerts its chemopreventative effects.

Anticancer Res. 2002 Nov-Dec;22(6C):4179-81

Issue # 66.3 - Homocysteine Lowering

Folic acid supplementation for coffee drinkers?

Elevated levels of plasma homocysteine (tHcy) are identified as independent risk factors for coronary heart disease and foetal neural tube defects. tHcy levels are negatively associated with folic acid intakes but increase as a result of coffee consumption. The ability of folic acid supplementation to eliminate the tHcy-elevating effect of coffee was investigated in a recent randomised, blind study. A total of 121 healthy non-smoking subjects (male and female, aged 29-65 years) participated in the trial. The effects of consuming 600ml coffee per day in combination with placebo were compared with the effects of consuming 600 ml per day in combination with a folic acid supplement (200ug per day). It was concluded that supplementation with 200ug of folic acid eliminates the tHcy increasing effect of 600ml of filtered coffee.

Eur J Clin Nutr. 2003 Nov;57 (11):1411-7.

Associated with decreased homocysteine?

Hyperhomocysteinemia is a frequent finding after cardiac transplantation, but increased folate intake induces a decrease in total homocysteine concentrations. In 1998, food in Canada was fortified nationwide with folic acid. A study assessed the impact of routine folate fortification on homocysteine concentrations in our cardiac transplant population. In 18 subjects, they measured total homocysteine (tHcy), serum folate, and cobalamin concentrations in 1997 (before folate fortification) and in 1998 (after fortification). They repeated the analysis after specific multivitamin supplementation for 10 weeks. National folate fortification was associated with decreased tHcy and increased folate concentrations in the cardiac transplant population. Additional administration of vitamin supplements induced a further decrease in tHcy and an increase in folate.

J Heart Lung Transplant. 2004 Apr;23(4):405-12

Issue # 66.2 - Ginkgo Biloba for Vitiligo and Raynauds

Ginkgo biloba for vitiligo?

A recent clinical trial evaluated the efficacy of Ginkgo biloba in controlling the activity of the disease process in patients with limited and slow-progressing vitiligo and in inducing repigmentation in affected areas. A total of 47 patients completed the double-blind randomised control trial and each was assigned to one of two treatment groups, receiving either Ginkgo biloba 40mg three times/day (group A) or placebo (group B). A significant cessation of active progression of depigmentation was observed in those treated with the Ginkgo biloba. Marked to complete repigmentation was seen in 10 patients in group A compared with only 2 patients in group B. It was concluded that Ginkgo biloba is a safe and fairly effective treatment for arresting the progression of vitiligo.

Clin Exp Dermatol. 2003 May;28(3):285-7.

Ginkgo biloba and Raynaud\'s disease

A double-blind placebo-controlled trial Ginkgo biloba is reputed as having an ability to improve circulation and so is often recommended in the treatment of Raynaud\'s disease - a painful condition that is episodic in its nature and is characterised by inadequate blood flow to the extremities. The efficacy of a standardised Ginkgo biloba extract in the treatment of Raynaud\'s disease was investigated in a randomised double-blind placebo controlled trial. After a two-week assessment period, patients received treatment with Ginkgo biloba extract or placebo over a 10-week period. Patients recorded the frequency, duration and severity of their attacks over the 12-week period. It was concluded that Ginkgo biloba may be effective in reducing the number of attacks per week in patients suffering from Raynaud\'s disease.

Vasc Med. 2002; 7(4):265-7.

Issue # 66.1 - Benefits of Anti Oxidants

Antioxidants and physical performance in elderly persons

A study was carried out to assess the correlation of plasma concentrations and daily intakes of antioxidants with skeletal muscle strength and physical performance in the elderly. 986 Italians aged over 65 had their physical performance assessed on the basis of walking speed, ability to rise from a chair, standing balance and knee extension. A questionnaire was used to evaluate the daily dietary intakes of vitamin C, vitamin E, B-carotene, and retinol. Of the daily dietary intake measures, vitamin C and B-carotene were significantly correlated with knee extension strength, and vitamin C was significantly associated with physical performance. This shows that plasma antioxidant concentrations correlate positively with physical performance and strength. Higher dietary intakes of most antioxidants, especially vitamin C, appear to be associated with higher skeletal muscular strength in elderly persons.

Am J Clin Nutr 2004;79:289-94

Benefit to endurance athletes?

The influence of an antioxidant vitamin supplement on immune cell response to prolonged exercise was determined using a randomized, double-blind, placebo-controlled, cross-over study. Following a 3-week period during which subjects ingested a multivitamin and -mineral complex sufficient to meet the recommended daily allowance, they took either a placebo or an antioxidant vitamin supplement containing 900 mg vitamin C and other antioxidants. Blood samples were drawn prior to and immediately following exercise. Plasma vitamin C, vitamin E, and beta-carotene concentrations significantly increased following 7-day supplementation. Although the impact of exercise on neutrophil function is multifactorial, the data suggest that antioxidant supplementation may be of benefit to endurance athletes for the maintenance of this particular function of the innate immune system following the 7-day supplementation period.

Int J Sport Nutr Exerc Metab. 2003 Sep;13(3):369-81

Antioxidant supplementation and Alzheimer\'s disease

It has been suggested that antioxidants may protect the ageing brain against oxidative damage associated with pathological changes of Alzheimer disease and a recent study set out to test this hypothesis. The relationship between the use of antioxidant supplements and the risk of Alzheimer\'s disease was examined in a cross-sectional and prospective study involving 4740 subjects aged 65 years or older. From the results, the authors concluded that the use of vitamin E and C supplements in combination was associated with a reduced prevalence and incidence of Alzheimer\'s disease and that antioxidant supplements merit further study as agents for the primary prevention of Alzheimer\'s disease.

Arch Neurol. 2004 Jan;61(1):82-8.

Vitamin C supplementation, smoking and infertility treatment

A recent prospective study investigated the influence of vitamin C supplementation on the outcome of infertility treatment with in vitro fertilisation and embryonic transfer in females. 76 women participated in the study (38 smokers, 38 non-smokers), half of the subjects (19 smokers and 19 non-smokers) were assigned to take 500mg in a form allowing for gradual release over 8 - 12 hours. The control group consisted of the same number of smokers and non-smokers. The success of the infertility treatment was evaluated based on the number of pregnancies. The results showed that vitamin C supplementation resulted in a higher number of pregnancies and that this effect was greatest in the non-smokers group. Overall the pregnancy rate was significantly higher in the non-smoking group, which provides a reason for asking women to give up smoking before undergoing infertility treatment.

Cent Eur J Public Health. 2003 Jun;11(2):63-7