^ Fortmann, SP; Burda, BU; Senger, CA; Lin, JS; Whitlock, EP (Nov 12, 2013). "Vitamin and Mineral Supplements in the Primary Prevention of Cardiovascular Disease and Cancer: An Updated Systematic Evidence Review for the U.S. Preventive Services Task Force". Annals of Internal Medicine. 159 (12): 824–834. doi:10.7326/0003-4819-159-12-201312170-00729. PMID 24217421.
Poor nutrition can manifest itself in many ways. The more obvious symptoms of a nutritional deficiency include dull, dry or shedding hair; red, dry, pale or dull eyes; spoon-shaped, brittle or ridged nails; bleeding gums; swollen, red, cracked lips; flaky skin that doesn't heal quickly; swelling in your legs and feet; wasted, weak muscles; memory loss; and fatigue.
Talk to your doctor if you don’t think you’re getting enough vitamins and minerals in your diet. They can help you decide which micronutrients you need. They also can recommend a dietary supplement. This will depend on your overall health and lifestyle. Supplements can cause problems with cancer treatments or surgery. Your doctor will know if they interact with any health conditions you have.
FDA regulations for nutritional supplements differ in important ways from those for prescription or over-the-counter drugs. For one thing, pharmaceutical companies have to gather data showing that a new drug is safe and effective in order to get the FDA's approval to market the drug. Makers of dietary supplements don't have to show that sort of proof. Be sure to let your doctor know about any nutritional supplement you plan on taking so you can discuss whether it's right for you and the appropriate dose.
Those who want to use natural healing methods, such as the use of food and supplements of essential nutrients to prevent or reverse illness, should consult therapists who are qualified to give advice on how natural therapies can help. I recommend that anyone interested in supplements read the references for this article as well as the archives of the Journal of Orthomolecular Medicine http://orthomolecular.org/library/jom/ and the Orthomolecular Medicine News Service http://orthomolecular.org/resources/omns/index.shtml . Both are free access online.
The soil in areas with relatively low rainfall may in some cases contain an extremely high concentration of minerals, which is reflected in the plants growing there. This was well documented 70 years ago in the book Tomorrow's Food.  The Dentist George W. Heard found that the soil in Hereford, Texas, was exceptionally rich in minerals. Hereford became known as the "town without a toothache" after a newspaper article from January 29, 1942, reported that Hereford had the lowest incidence of tooth decay of any city in the United States.  Heard found that people in Hereford had exceptionally few dental cavities and also that the soil locally was especially rich in minerals. He emphasized that the population in the county ate unprocessed food and was drinking raw milk. 
Some supplements that were found to have health benefits in observational studies turned out, with more rigorous testing, to be not only ineffective but also risky. Vitamin E, which was initially thought to protect the heart, was later discovered to increase the risk for bleeding strokes. Folic acid and other B vitamins were once believed to prevent heart disease and strokes—until later studies not only didn't confirm that benefit but actually raised concerns that high doses of these nutrients might increase cancer risk.
Omega-3 fatty acids are essential for the neurological and early visual development of your baby and for making breast milk after birth. Aim for two weekly servings of cold water fish such as salmon, tuna, sardines, herring, or anchovies. Sardines are widely considered the safest and most sustainable fish to eat, while seaweed is a rich vegetarian source of Omega-3s.
Watch your portion sizes: Check to see what the recommended portion sizes of foods you eat looks like in the bowls, plates, and glasses you use at home. When dining out avoid "supersizing" your meal or buying "combo" meal deals that often include large-size menu items. Choose small-size items instead or ask for a take home bag and wrap up half of your meal to take home before you even start to eat.
As women, many of us are prone to neglecting our own dietary needs. You may feel you’re too busy to eat right, used to putting the needs of your family first, or trying to adhere to an extreme diet that leaves you short on vital nutrients and feeling cranky, hungry, and low on energy. Women’s specific needs are often neglected by dietary research, too. Studies tend to rely on male subjects whose hormone levels are more stable and predictable, thus sometimes making the results irrelevant or even misleading to women’s needs. All this can add up to serious shortfalls in your daily nutrition.
Nutritional supplements are exactly that, supplements to a healthy, nutritious diet. One should not take nutritional supplements in the hope that they will make up for a poor diet and lack of exercise, they will not! There are some nutritional supplements including some vitamins and minerals, as well as other nutrients/cofactors that one can use in conjunction with a healthy diet to promote optimal health. For example, to consume the amount of vitamin E that has been shown to protect the body against free radical damage, one would have to consume a very significant amount of fat calories as vitamin E is found in foods that are high in fat such as vegetable oils, nuts and seeds. it makes sense to take a supplement of vitamin E rather than consuming lots of fat. The same goes for vitamin D. It's very difficult to get vitamin D in your diet as it isn't found in many foods and studies show that most people do not get enough vitamin D.