Vitamins, Minerals & Phytochemicals
Your body needs approximately 29 vitamins and minerals to stay healthy and strong . Eating food is the best way and the most enjoyable method of meeting your nutrient needs and preventing disease . But there are certain circumstances when vitamin supplements can be a good idea . Many people ask if they should take supplements . This chapter should help you make some decisions . Along with vitamins and minerals, phytochemicals (natural plant substances) are also getting a lot of attention in the scientific community and understandablyso . Evidence is mounting that they play important roles in preventing cancer, heart disease and other chronic diseases . Let’s explore the amazing world of vitamins, minerals and phytochemicals.
When supplements may be needed:
If you do not eat the servings recommended from each of the four food groups of Canada’s Food Guide then a multivitamin/mineral supplement can help meet your needs . But remember that no supplement or combination of supplements can make up for a poor diet .
If you consume less than two milk products a day then consider taking a calcium supplement . The Osteoporosis Society of Canada recommends an intake of 1000mg for those aged 19 to 49, and 1000 to 1500 mg for those over 49 to help prevent osteoporosis . Calcium may also play a role in controlling high blood pressure, offer protection against colon cancer and is now being investigated for its potential role in decreasing PMS symptoms . If you take a calcium supplement, do not take more than 500 mg at a time to help maximize absorption.
Food Sources of Calcium
All women in the childbearing years should discuss folic acid supplements with their doctor and take a daily supplement containing 0 .4 mg of folic acid (folacin) . Research now shows that an increased intake of folic acid reduces the risk of birth defects, called neural tube defects, like spina bifida . Health and Welfare Canada recommends that if you are planning a pregnancy or suspect you may already be pregnant, talk to your doctor about folic acid supplements as early as possible . All women who become pregnant should take care to choose more foods higher in folate . These include dark green vegetables such as broccoli, asparagus, Brussels sprouts, and dark salad greens, orange juice, legumes and wheat germ .Ideally, daily folic acid supplements should be taken at least one month prior to conception and through the first trimester of pregnancy
Strict vegetarians who exclude all animal products, including meat, chicken, fish, eggs and milk products, should take a B12 supplement of 2 mcg per day unless they drink fortified soy milk daily . If you want to rely on soy milk for your B12 intake, make sure it is fortified with B12 by reading the label and drink enough to get 100% of your daily recommended intake .Strict vegetarians may also consider taking a multivitamin/mineral supplement unless their diet is well planned .
Pregnant women may benefit from the iron and calcium in a prenatal vitamin supplement, since their needs increase substantially for these two minerals during pregnancy .
Those who do not drink milk and get limited sun exposure would benefit from a vitamin D supplement of 100 to 400 IU per day.
The human body is continually using oxygen to stay alive .This use of oxygen produces free radicals, which are damaging compounds that can increase the risk of heart disease, cancer and other chronic diseases . Your body naturally combats free radicals and gets help from antioxidants found in food . The problem arises when free radicals outnumber antioxidants . A variety of external factors promote free radical formation: cigarette smoke, alcohol, ultraviolet light and air pollutants.
Vitamin C, vitamin E and beta carotene are three nutrients that act as antioxidants . There is some evidence, not conclusive however, that these vitamins decrease the risk of cancer and heart disease . For many scientists, the question still remains Vitamin whether antioxidant supplements should be routinel yrecommended . It also seems that these vitamins may work best when combined with certain foods, rather than just being taken as single supplements . Some scientists suggest that we don’t know enough about antioxidants to be able to safely recommend supplementation . Only one scientific body of nutrition experts, the University of California at Berkeley, recommends taking 250 to 500 mg of vitamin C and 200 to 800 IU of vitamin E daily . They also recommend that smokers avoid taking beta-carotene supplements because some research suggests that they increase the risk of lung cancer . If you are at risk for heart disease, you may benefit from a vitamin E supplement but first discuss it with your physician . Vitamin E can negatively interact with anticoagulant medications.
Five servings of fruits and vegetables daily, especially the dark green, yellow and orange ones, can give you a good dose of antioxidants.
Vitamin C and Smoking
Smoking robs the body of vitamin C, so the minimum recommended intake for smokers is about 60 to 80 mg per day instead of the usual 30 to 40 mg for non-smokers . Cigarette smoke is a major source of free radicals that damage cells and increase your risk of developing cancer and heart disease . If you cannot quit, or if you live with someone who smokes, all the more reason to eat lots of fruits and vegetables . Smarter still, make your life smoke-free . Don’t put off kicking the habit.
Iron carries oxygen around the body, and makes new cells, enzymes and hormones . Iron deficiency can result in anemia with symptoms including a loss of energy, loss of appetite, decreased immune function and the tendency to feel cold .Those at higher risk for anemia include menstruating women, endurance athletes, and vegetarians and teenage athletes who do not eat meat . If you suspect you have anemia, visit your physician to confirm it . Taking iron supplements could do unnecessarily harm to those prone to iron overload.
Generally, a diet that follows Canada’s Food Guide and includes a variety of foods will help prevent anemia . If prone to anemia a couple servings weekly of lean red meat can help . To enhance the absorption of iron from vegetable sources, consume a food high in vitamin C at the same time . Most colourful fruits and vegetables provide vitamin C, such as oranges, kiwis, cantaloupe, strawberries, and broccoli . So having an orange with your breakfast cereal and tomato sauce with your pasta will boost iron absorption.
B Vitamins and Heart Disease
High levels of homocysteine, an amino acid that everyone produces, is being linked to heart disease . Normally homocysteine is converted into non-damaging amino acids by three B vitamins: folate (folic acid), B6 and B12 . If the conversion does not take place quick enough or there is a lack of B vitamins, then the result could be an increased risk of heart disease . If you eat well, you are probably getting enough of these vitamins . If you do not, then you may want to consider taking a multivitamin supplement.
Most scientific bodies of nutrition experts do not recommended routine vitamin supplementation to ensure health .If you do choose to take them, here are some guidelines to follow:
• Choose a general multivitamin/mineral supplement that provides about 100% of the recommended nutrient intake (RNI) .
• Do not buy supplements that contain excessive amounts of vitamins and minerals . Some minerals can decrease the absorption of others . For example, zinc interferes with copper and calcium absorption, iron hinders zinc absorption and so on .
• For maximum tolerance and absorption take your multivitamin with or after a meal . If you take a multivitamin that contains iron and separate calcium supplements, take them at different times since these two minerals compete for absorption .
• There is no proof that chelated or colloidal minerals are better absorbed .
• Most time-released supplements dissolve too slowly to be completely absorbed
• In large doses, certain vitamins and minerals can be toxic .This is especially true for vitamin A, vitamin D, vitamin B6, iron and selenium so be careful not to overdo it . Pregnant women should take note—even a relatively low dose of vitamin A supplements can harm the developing fetus
Sulforaphane, lycopene and bioflavinoids are just a few of the hundreds of phytochemicals naturally occuring in plant foods that may be protective against cancer . A diet with plenty of whole grains, fruits and vegetables, soybean products, legumes and herbs and spices will ensure a good dose of phytochemicals . Below is a list of foods you will want to incorporate into your diet regularly to help protect your health . It is likely that many more phytochemicals are still waiting to be discovered.