In most women folate, a type of B vitamin, reduces the risk of breast cancer. However, in women with a certain genetic make-up it has shown to be the opposite: folate raises the risk of breast cancer.
“Therefore I think it is too soon to introduce a general fortification of foodstuffs with folic acid”, says nutrition researcher Ulrika Ericson of Lund University.
Neither does she think it is a good idea to take multivitamin tablets and other dietary supplements containing folic acid (the synthetic form of folate) without special reason.
“It is better to eat a diet containing a lot of fruit, vegetables, legumes and wholemeal products. Then you get sufficient quantities of the natural form of folate, other vitamins and dietary fibre.”
In her doctoral thesis, Ulrika Ericson has taken as her starting point the major study from the 1990s, Malmö Diet and Cancer, which gathered information and blood samples from over 17 000 women. At the end of 2004, just over 500 of these women had developed breast cancer. Folate levels, genetic make-up and food habits in the breast cancer patients have then been compared with the corresponding data from the healthy women.
Those women whose intake of folate corresponded to the level recommended in Sweden had only half as great a risk of getting breast cancer as those who had the lowest intake of folate. This was the overall finding, which shows that folate generally protects against breast cancer. However, the breast cancer risk increased in line with folate levels for a specific sub-group among the women – those who had inherited a certain variant of an enzyme that affects how folate is used in the body.
The ten per cent of the women who had inherited this variant from both of their parents had the highest risk of breast cancer, particularly if they also took vitamin tablets containing folic acid.
“No-one knows which genetic variant of this enzyme they have. This is why I think people should only take dietary supplements if there is a particular reason to do so, not just because 'it's probably a good idea'”, says Ulrika Ericson.
She considers that there are two groups who could have a particular reason to take a folic acid supplement. These are people with a certain type of anaemia and low folate levels and women who are trying to become pregnant (folate reduces the risk of neural tube defects in babies).
To be on the safe side, others should avoid vitamin tablets containing folic acid while it is still unclear what the link is between folate and different types of cancer. Mandatory folic acid fortification of foodstuffs, which has been discussed in many countries including Sweden, is not appropriate in the current situation, according to Ulrika Ericson.
Researchers analyzed 84 hours of primetime and 12 hours of Saturday morning broadcast television over a 28-day period in 2004. ABC, CBS, Fox and NBC were sampled on a rotating basis to develop a complete profile of each network. The Saturday-morning cartoon segment (from 8:00 am to 11:00 am) was included to capture food advertisements marketed primarily to children.
All 96 hours of observations were videotaped and reviewed later to identify food advertisements and specific food items being promoted. Only food items that were clearly promoted for sale during an advertisement were recorded. Each food item was then analyzed for nutritional content. Observed portion sizes were converted to the number of servings.
The article indicates that the observed food items fail to comply with Food Guide Pyramid recommendations in every food group except grains. The average observed food item contained excessive servings of sugars, fat, and meat and inadequate servings of dairy, fruit and vegetables. The situation was similar for essential nutrients, with the observed foods oversupplying eight nutrients: protein, selenium, sodium, niacin, total fat, saturated fat, thiamin and cholesterol. These same foods undersupplied 12 nutrients: iron, phosphorus, vitamin A, carbohydrates, calcium, vitamin E, magnesium, copper, potassium, pantothenic acid, fiber, and vitamin D.
The authors advocate nutritional warnings for imbalanced foods similar to those mandated on direct-to-consumer drug advertisements. They recommend investigating health promotion strategies that target consumers, the food industry, public media, and regulation focusing on a three-pronged approach.
“First, the public should be informed about the nature and extent of the bias in televised food advertisements. Educational efforts should identify the specific nutrients that tend to be oversupplied and undersupplied in advertised foods and should specify the single food items that surpass an entire day's worth of sugar and fat servings. Second, educational efforts should also provide consumers with skills for distinguishing balanced food selections from imbalanced food selections. For example, interactive websites could be developed that test a participant's ability to identify imbalanced food selections from a list of options. This type of game-based approach would likely appeal to youth and adults. Third, the public should be directed to established nutritional guidelines and other credible resources for making healthful food choices.”
Led by researchers at Copenhagen University in Denmark, Robbins and an international team of colleagues analyzed the results of seven large clinical trials from around the world to assess the effectiveness of vitamin D alone or with calcium in reducing fractures among people averaging 70 years or older. The researchers could not identify any significant effects for people who only take vitamin D supplements.
Among the clinical trial results analyzed was Robbins' WHI research, which was part of a 15-year, national program to address the most common causes of death, disability and poor quality of life in postmenopausal women such as cardiovascular disease, cancer and osteoporosis. Those trials were primarily designed to study the effect of calcium and vitamin D supplementation in preventing hip fractures, with a secondary objective of testing the supplements on spine and other types of fractures, as well as on colorectal cancer. The results were published in the Feb. 16, 2006 edition of the New England Journal of Medicine.
Fractures are a major cause of disability, loss of independence and death for older people. The injuries are often the result of osteoporosis, or porous bone, a disease characterized by low bone mass and bone fragility. The National Osteoporosis Foundation estimates that about 10 million Americans have osteoporosis; 80 percent of them are women. Four of 10 women over age 50 will experience a fracture of the hip, spine or wrist in their lifetime, and osteoporosis-related fractures were responsible for an estimated $19 billion in health-related costs in 2005.
“This study supports a growing consensus that combined calcium and vitamin D is more effective than vitamin D alone in reducing a variety of fractures,” said Robbins. “Interestingly, this combination of supplements benefits both women and men of all ages, which is not something we fully expected to find. We now need to investigate the best dosage, duration and optimal way for people to take it.”
Patients who use vitamin supplements also showed lower levels of plasma homocysteine than in patients who did not (P = 0.001) or healthy controls (P = 0.003). Vitamin B6 and folate were both associated with homocysteine levels, whereas vitamin B12 was not. Twenty-four (48%) of 50 controls and 23 (50%) of 46 of the celiac disease patients carried the MTHFR thermolabile variant T-allele (P = 0.89).
The research team concludes that Homocysteine levels are dependent on Marsh classification and the regular use of B-vitamin supplements reduces of homocysteine levels in patients with celiac disease.The study confirms earlier studies suggesting that both the presence and severity of celiac disease determined homocysteine levels.
The regular use of supplemental B vitamins resulted in higher levels of serum vitamin B6, folate, vitamin B12 and lower levels of plasma homocysteine in patients with celiac disease. Moreover, supplemental B vitamins seem to offer protection against the effects of villous atrophy on homocysteine levels, independent of the genetic susceptibility status as determined by carriage of the C677T polymorphism of 5,10 methylenetetrahydrofolate reductase.
World J Gastroenterol. 2009;15:955–960
Since the 1960s, researchers have been studying how the water-soluble vitamin supports the healthy functioning of cells. They discovered that it's essential for cell division and replication, making it especially important for expectant mothers.
It's also important to proper replication of DNA and RNA — a lack of folate has been linked to genetic mutations that can lead to cancer.
Folate is commonly found in leafy green vegetables like spinach and turnip greens. Since 1998, the U.S. Food and Drug Administration has mandated that many foods, such as rice, flour and cornmeal, be enriched with a synthetic folate known as folic acid.
While folate deficiency is no longer a problem in the U.S., it remains widespread in developing nations and much of Europe, where enriching grain products is not widely practiced.
This new research, funded by the National Science Foundation and originally sparked by funding from the U.S. Department of Energy, links folate to the production or repair of compounds called iron-sulfur clusters through a recently discovered intermediary protein called COG0354.
These clusters are part of the mechanism cells use to produce energy and carry out other vital reactions. But they are also sensitive to a byproduct of the energy-producing process: highly reactive oxygen-based molecules, some of which are called free radicals.
The oxidative stress caused when these molecules pollute a cell has been linked to cell death and aging, as well as to conditions such as atherosclerosis, Parkinson's disease, heart disease, Alzheimer's, fragile X syndrome and many more.
Examining the folate-iron-sulfur cluster link required the team to pull experience from not only UF's microbiology and cell science and food science and human nutrition departments, but also the McKnight Brain Institute and the National High Magnetic Field Laboratory.
Expertise from the latter two institutions was needed because the researchers used nuclear magnetic resonance analysis to observe folate interacting with COG0354 protein — molecular-scale activity that could otherwise only have been shown indirectly, said Arthur Edison, the NHMFL's director of chemistry and biology and an associate professor with UF's biochemistry and molecular biology department.
The researchers have found that COG0354 is present in creatures from each of the six kingdoms of life, from mice and plants to one-cell organisms that may predate bacteria.
The findings will open new avenues of study into the overall mechanism of oxidative stress repair, and may someday lead to new medicines. For now, the researchers emphasize that this is another example of the vitamin's importance in one's diet.
Vitamin D, the “sunshine” vitamin, does a lot more than help keep bones strong — scientists are finding that it impacts all aspects of our health.
Vitamin D can be obtained from exposure to sunlight, vitamin supplements (vitamin D-3 is recommended by many experts), and foods such as salmon and tuna.
Recent studies show that having high levels of vitamin D in our blood can help protect against many diseases, while low levels are linked with several disorders.
Here are 12 critically important ways vitamin D can help protect your health:
1. Colon cancer. A study by cancer prevention specialists at the Moores Cancer Center at the University of California found that high amounts of vitamin D could slash colorectal cancer rates by two-thirds. A European study found that high levels of vitamin D cut the odds of colon cancer by almost 40 percent.
2. Breast cancer. Research using data from two earlier studies found that women with the highest amounts of vitamin D in their blood lowered their risk of breast cancer by 50 percent when compared to women with the lowest levels. A Canadian study found that women who took a vitamin D pill of least 400 international units every day lowered their risk of developing breast cancer by 24 percent.
3. Heart disease. A British study has found that middle-aged and elderly people with high levels of vitamin D reduce their risk of developing cardiovascular disease by 33 percent. Utah scientists found that patients who raised their blood levels of vitamin D after being diagnosed as deficient lowered their risk of having a heart attack by 33 percent, their risk of heart failure by 20 percent, and their risk of dying from any cause by 30 percent.
4. Brain health. A European study of men between the ages of 40 and 79 found that high levels of vitamin D were associated with high scores on memory tests.
5. Diabetes. Researchers at Warwick Medical School found that adults with the highest blood levels of vitamin D lowered their risk of developing Type 2 diabetes by 55 percent.
6. Asthma. Asthmatics who have high levels of vitamin D have better lung function and respond to treatment better than those who have low levels, according to researchers at National Jewish Health in Denver.
7. Bone health. Vitamin D and calcium reduce the risk of hip fractures in the elderly. Studies show that people who are deficient in vitamin D absorb 65 percent less calcium than those with normal levels. One recent study from the United Kingdom found that 95 percent of patients with hip fractures were deficient in vitamin D, and having adequate levels could reduce hip fractures by up to 50 percent.
8. Depression. University of Toronto researchers found that people who suffer from depression, especially those with seasonal affective disorder, improved as the levels of vitamin D in the blood rose. Researchers in Norway found that high doses of vitamin D helped relieve the symptoms of depression.
9. Multiple sclerosis. Australian scientists discovered that people who live in the state furthest from the equator — and get less sunlight — are seven times more likely to develop multiple sclerosis than those who live in the sunniest state.
10. Colds and flu. Scientists at the University of Colorado found that people with the lowest amounts of vitamin D in their blood had the highest incidence of colds and flu.
11. Rheumatoid arthritis. Researchers from the University of Alabama, Birmingham, found that women with the highest levels of vitamin D in their blood lowered their chances of developing rheumatoid arthritis by 30 percent.
12. Crohn's Disease. Vitamin D switches on genes responsible for fighting Crohn's disease (a chronic inflammatory disease primarily affecting the small and large intestine), according to Canadian researchers. “Our data suggests that vitamin D deficiency can contribute to Crohn's disease,” Dr. John White, endocrinologist at the Research Institute of the McGill University Health Center in Montreal, Canada, said in a statement.
(Source: National Institute of Health UK)
Ms. Agler and colleagues reviewed data compiled by the Women's Health Study, a multi-year, long-term effort ending in 2004 that focused on the effects of aspirin and vitamin E in the prevention of cardiovascular disease and cancer in nearly 40,000 women aged 45 years and older. Study participants were randomized to receive either 600 mg of vitamin E or a placebo every other day during the course of the research.
Although fewer women taking vitamin E developed COPD, Ms. Agler noted the supplements appeared to have no effect on asthma, and women taking vitamin E supplements were diagnosed with asthma at about the same rate as women taking placebo pills. Importantly, Ms. Agler noted the decreased risk of COPD in women who were given vitamin E was the same for smokers as for non-smokers.
Ms. Agler said further research will explore the way vitamin E affects the lung tissue and function, and will assess the effects of vitamin E supplements on lung diseases in men. “If results of this study are borne out by further research, clinicians may recommend that women take vitamin E supplements to prevent COPD,” Ms. Agler noted. “Remember that vitamin E supplements are known to have detrimental effects in some people; for example vitamin E supplementation increased risk of congestive heart failure in cardiovascular disease patients. Broader recommendations would need to balance both benefits and risks. “
In the current study, vitamin K2 — which study participants most frequently got through cheese — was linked to the odds of developing or dying from cancer, whereas vitamin K1 was not.
The findings are based on data from 24,340 German adults who were between the ages of 35 and 64, and cancer-free at the outset. The researchers estimated the participants' usual vitamin K intake based on a detailed dietary questionnaire. Over the next decade, 1,755 participants were diagnosed with colon, breast, prostate or lung cancers, of whom 458 died during the study period.
In general, the researchers found, the one quarter with the highest intakes of vitamin K2 were 28 percent less likely to have died of any one of the cancers than the one-quarter of men and women with the lowest intakes of the vitamin. That was with factors like age, weight, exercise habits, smoking and consumption of certain other nutrients, like fiber and calcium, taken into account.
Of the one-quarter of study participants who got the least vitamin K2, 156 — or 2.6 percent — died of one of the four cancers. That was true of 1.6 percent of participants with the highest intakes of the vitamin from food.
When Linseisin's team looked at the cancer types individually, there was no clear link between either form of vitamin K and breast cancer or colon cancer. However, greater consumption of vitamin K2 was linked to lower risks of developing or dying from lung cancer — a disease for which smoking is the major risk factor — or of developing prostate cancer.
Of the one-quarter of study participants with the lowest vitamin K2 intakes, 47 — or 0.8 percent — developed lung cancer, versus 0.4 percent of the one-quarter who got the most vitamin K2 in their diets. When it came to prostate cancer, there were 111 cases among the one-quarter of men with the lowest vitamin K2 intakes, and 65 cases in the group with the highest consumption.
In theory, vitamin K itself could offer some protection against cancer. It's often used to counteract too-high doses of blood thinners, although this does not have an obvious link to cancer. In lab research, however, Linseisin and his colleagues point out, the vitamin has been shown to inhibit cancer cell growth and promote apoptosis — a process by which abnormal cells kill themselves off.
But whether vitamin K intake itself is responsible for the lower cancer risks in this study is unclear, according to the researchers. One limitation is that they estimated vitamin K intake based on participants' reported eating habits; most of their vitamin K came from eating cheese, and it's possible, Linseisin and his colleagues note, that some other components of that food are related to cancer risk.
Future studies, the researchers say, should measure people's blood levels of vitamin K and look at the relationship of those levels with cancer risks.
SOURCE: American Journal of Clinical Nutrition
Some people may be at risk of not getting enough vitamin D because they don’t get enough in their diet or because they have more limited sun exposure which reduces the amount of vitamin D their bodies make. Those at risk include:
Breastfed infants require 400 IU vitamin D per day from birth. Because breast milk is naturally low in vitamin D and infants are not usually exposed to the sun, a vitamin D supplement of 400 IU is recommended. Healthy term infants fed infant formula do not require a vitamin D supplement as it is already added to the formula.
- Pregnant women should consume vitamin D from food (for example, from a least 3 glasses of milk der day) or supplements (usually 200-400 IU is provided in a supplement) to ensure the baby is born with optimal vitamin D in their body. If a supplement is taken, be sure not to exceed 2000 IU vitamin D per day.
- Adults over 50 years may not prodce vitamin D in skin as well as when they were younger. It is recommended that adults (men and women) over 50 years take a supplement of 400 IU / day.
- People with skin darkly pigmented with melanin are less able to make vitamin D from exposure to sunlight. Since many people with darker skin colour also avoid vitamin D fortified milk due to lactose intolerance, their dietary intake of the vitamin may be low, so extra vitamin D, such as the amount typically found in a general multivitamin-mineral supplement (200-400 IU) would be a good idea.
- People with limited sun exposure sun exposure is limited due to mostly living or working indoors, wearing clothing such as long robes and head coverings, then it is wise to carefully choose vitamin D rich foods (see above) or to take a vitamin D supplement, such as the amount typically found in a general multivitamin-mineral supplement (200-400 IU).
Some medical conditions such as Crohn's disease, cystic fibrosis, celiac disease, surgical removal of part of the stomach or intestines, and some forms of liver disease, interfere with absorption of vitamin D. Being overweight and obese causes fat to stay stored in fat tissues and not be released into the blood, preventing vitamin D from being available to the body. If you have one of these conditions, check with your doctor to ask if a vitamin D supplement is needed.
Can I take too much vitamin D?
Yes. Too much vitamin D can be harmful. The total daily intake from food and supplements combined should not exceed 1000 IU for infants and young children and 2000 IU for adults.
The Bottom Line
Most people, except those in the risk groups noted above, can get enough vitamin D if they eat enough vitamin D rich foods (for example, milk, vitamin D fortified foods and some fatty fish) and if they engage in safe sun practices. If you are concerned about your vitamin D status, discuss the issue with Nastaran.
Source: Dietitians of Canada. Reproduced with Permission. Note: The Australian adequate intake is 200 IU however Nastaran recommends 400 IU as per the Canadian recommended intake.
Reduced mobility can result in overweight or obesity, because you are using fewer calories. Some medications, like steroids and antidepressants can also cause weight gain.
Being underweight and having poor nutrition can be caused by
– reduced mobility and feeling tired, which can make shopping, cooking and eating difficult
– difficulty getting food or drinks to the mouth
– poor appetite, and
– difficulty swallowing.
If you are having any of these symptoms and they are keeping you from eating, discuss your symptoms with your doctor.
When you have MS, it is especially important to get the recommended amounts (the Dietary Reference Intakes, or DRIs) of the following vitamins and minerals. If your doctor has diagnosed that you are deficient in any of these, you may be advised to take more. Do not take amounts higher than what is recommended because this can be harmful.
– Calcium and vitamin D. People with MS have a higher risk of low bone mineral density and breaking bones. This may be due to low vitamin D and calcium in the diet, or other factors such reduced physical activity, such as walking. Good food sources of calcium include dairy products (milk, yogurt and cheese), fortified soy and rice beverages, fortified juices, tofu with added calcium and canned fish with the bones. Good food sources of vitamin D include milk, fortified soy and rice beverages, fortified juices, fatty fish, such as salmon, and eggs. If you do not eat these foods daily, you should discuss adding a daily supplement with your doctor or dietitian.
– Vitamin B12. Vitamin B12 deficiency is common in people with MS. Low levels of vitamin B12 can cause a type of anemia that can make you feel tired. Good food sources of vitamin B12 are dairy products (milk, yogurt and cheese), eggs, meat, fish, poultry, and fortified soy and rice beverages. It is recommended that people over 50 take a vitamin B12 supplement, because as you get older, you don't absorb the vitamin B12 from food very well. The amount of vitamin B12 in a multivitamin is usually enough.
– Zinc and selenium. Zinc and selenium deficiencies are common in people with MS. Zinc is needed for the growth and repair of body cells. Selenium works as an antioxidant to protect body cells from damage. Good food sources of zinc are meat, seafood, dried beans, peas, and lentils, and whole grains. Good food sources of selenium are Brazil nuts, seafood, fish and shellfish, liver and kidney. If these are foods that you don't eat regularly, you may need a supplement. The amounts in a multivitamin mineral supplement are usually enough.
Many people with MS try different herbal or nutritional supplements hoping these will improve their symptoms or prevent MS from getting worse. Ginkgo biloba has been studied in people with MS, and while early studies show some benefit, larger studies need to be done before it can be recommended. Gingko biloba has many side effects and shouldn't be taken by people who have bleeding disorders, who are taking blood thinning medication, or who are planning surgery.
Other supplements, including St. John's wort, ginseng, echinacea and valerian, have not been studied in people with MS, so it is not known if they are effective or safe. Because echinacea can stimulate the immune system, it might make MS symptoms worse.
Source: Dietitians of Canada. Reproduced with Permission.