S

Selenium

Selenium is a trace element that helps activate the body’s own antioxidant enzymes. The average American gets nearly twice the daily requirement of selenium. Intakes marginally above the upper limit (400mcg/day) can cause “selenosis,” characterized by hair and nail brittleness and loss. Selenium is also needed for the proper functioning of the thyroid gland and may play a role in fertility, especially in men. Preliminary research also suggests that selenium may reduce the risk of lung, liver and prostate cancers, and osteoporosis. Inadequate selenium has also been associated with impaired immune function. Top sources of selenium include Brazil nuts, fish, whole grains, wheat germ, and sunflower seeds. The amount of selenium in vegetables is dependent on the selenium content of the soil.

V

Vegetarianism

Most people associate vegetarianism with abstention from meat, but there are actually many variations:

• Pesco-Vegetarian: Eats plant-based foods, dairy and eggs plus fish, but not other types of meat.
• Lacto-Ovo Vegetarian: Eats plant-based foods, dairy and eggs, but not meat.
• Lacto-Vegetarian: Eats plant-based foods and dairy products like cheese and milk, but not eggs or meat.
• Vegan: Eats only plant-based foods, not dairy products, eggs, or meat.

Vegetarian diets are generally low in saturated fat and cholesterol. Not surprisingly, research shows vegetarian women weigh less than their carnivorous peers. Blood pressure also seems to be lower in those who chose non-meat protein sources. British researchers found that children with higher IQs were more likely to grow up to be vegetarians. However, vegetarian diets do run the risk of deficiency in the following nutrients, so make sure to get plenty of the plant sources listed.

• Protein: Soy (tofu, tempeh), whole grains, legumes, and nuts.
• Iron: Spinach, broccoli, dried beans, dried fruit, whole grains, fortified cereals, and brewer's yeast.
• Calcium: Arugula, broccoli, kale, soy and legumes.
• B vitamins: Mushrooms, legumes, oats, beans, and green leafy vegetables. However, vitamin B12 is only found in animal or fortified products so it is recommended that all vegetarians monitor their intake of this nutrient.
• Zinc: Beans, oats, green peas, fortified cereals, and sunflower seeds.

The 14 essential vitamins can be classified into two groups: fat-soluble and water-soluble. The fat-soluble vitamins include A, D, E and K, and have many functions, including promoting healthy eyes and bones. The water-soluble vitamins include all the B vitamins, choline and vitamin C. Most of these are involved in essential enzyme systems and energy metabolism. The word “vitamin” was invented by researchers studying beriberi, a disease caused by severe deficiency of vitamin B1 (thiamin). The researchers described a compound believed to act as a cure, as a “vital amine” after its chemical characteristics. Make sure you get vitamins from whole foods as taking vitamin supplement pills may pose health risks ranging from toxicity to nutrient displacement.
The Journal of Clinical Investigation found vitamin E pills actually increased LDL (bad) cholesterol in animal studies. A National Institutes of Health "state-of-the-science" panel found insufficient evidence on the benefits and safety of multivitamins/minerals to recommend their regular consumption.

About half of American adults do not get enough vitamin A, a nutrient needed for healthy skin - it helps maintain the epithelial tissues that make up the skin’s surface, eyesight - inadequate intake can lead to poor vision in dim light and possibly age-related macular degeneration, and immune function - vital for development of immune cells. Top sources include sweet potatoes, butternut squash, carrots, pumpkin, cantaloupe, pink and red grapefruit, spinach and kale.

B vitamins help convert food to energy and promote healthy skin, hair, muscles and brain function. Top sources include mushrooms, legumes, oats, beans, and green leafy vegetables. However, vitamin B12 is only found in animal sources (e.g. clams, oysters, sardines, and salmon) or fortified products and is often lacking in a strict vegetarian diet. Vitamin B6 helps with protein metabolism, red blood cell formation, DNA repair, and nervous and immune system function. Vitamin B12 deficiency has been linked to heart disease and stroke.

Vitamin C

Vitamin C is a potent antioxidant that promotes skin health by encouraging skin cell turnover and supporting collagen formation. Vitamin C also supports the immune system by enhancing white blood cell function and may also lower the severity and duration of colds by reducing free radicals and levels of histamine - a chemical responsible for congestion and stuffiness. Research shows vitamin C may promote bone health and enhance the body's absorption of iron as well. Also, Arizona State University researchers have reported that vitamin C may boost the body’s ability to metabolize fat.  A recent report from the U.S. Department of Agriculture (USDA) found that about 10% of American adults do not get enough of this nutrient. Top sources include red/yellow bell peppers, kiwi, oranges, broccoli, papaya, and strawberries, all of which provide well over 100% of the Daily Value of vitamin C per serving.

Vitamin D

Vitamin D plays a critical role in maintaining healthy bones, eyes, teeth and skin. The nutrient is unique in that our skin can create it from exposure to the sun. Since we need vitamin D to utilize calcium, low levels of the nutrient may lead to increased fracture risk and dental decay. Among those 50 and older, those with lowest vitamin D levels were found to have at least 25% more tooth loss. Researchers around the world are finding that vitamin D deficiency may contribute to other ailments, including breast, colon, pancreatic and prostate cancer, multiple sclerosis, hypertension and diabetes. Top sources include oysters, button mushrooms, sardines, fortified non-fat milk, and sunshine. In a dazzling dietary breakthrough, food researchers have figured out how to naturally boost vitamin D levels in mushrooms to over 100% of daily requirements, simply by exposing the mushrooms to more light.

Vitamin E

Vitamin E is a potent antioxidant that may slow the effects of aging and help bolster the immune system. It shields immune cells from free radicals and may boost the production of bacteria-busting white blood cells. A recent report from the U.S. Department of Agriculture (USDA) found that about 90% of American men and 97% of women do not get enough of this nutrient. But don't go reaching for the supplement shelf! The Lancet's large-scale review found that antioxidant pills, like vitamin E, increased overall mortality. Another report found vitamin E pills actually increased LDL "bad" cholesterol in animal studies. Top dietary sources include almonds, sunflower seeds, red bell peppers, butternut squash, and dark green leafy vegetables.

Vitamin K

Vitamin K is one of the four fat-soluble vitamins (A, D and E are the others). The "K" is derived from the German word "koagulation", which means "blood clotting." Vitamin K plays a major biological role because it enables the liver to manufacture prothrombin and other proteins that bind calcium and are necessary for blood clotting and bone crystal formation. Vitamin K has been linked to bone health and a reduced risk of bone fractures. The Framingham Heart Study found male and female seniors with a dietary intake of 250 micrograms of vitamin K per day had a 65% lower risk of hip fractures than those with an intake of 50mcg/day (adequate intake is 120mcg for men, 90mcg for women. Other research suggests vitamin K may play a role in inhibiting the growth of tumors. Some of the best sources of vitamin K include kale, collard greens, spinach, broccoli, Brussels sprouts, and chicory. The bacteria that line the gastrointestinal tract also make some vitamin K.

Zeaxanthin

Zeaxanthin is one of two yellow carotenoids (the other is lutein) found in the eye's retina that are believed to filter out harmful blue light and protect against age-related macular degeneration, the leading cause of blindness in people over 65. According to USDA researchers, zeaxanthin intake may also reduce the risk of certain types of cancer, especially of the lung and breast. Top sources include green leafy vegetables, orange peppers, and corn.

Zinc

Zinc plays a vital role in maintaining and repairing skin. This mineral is vital for normal growth, reproduction, taste and smell, as well as supporting immune function and promoting prostate and eye health. Unfortunately, one-third of Americans over 70 years old are zinc deficient. Top sources include oysters, crab, turkey, beans, oats, green peas, and sunflower seeds. Always favor food sources over supplements. The National Cancer Institute found that men who took more than 100 mg of zinc supplements daily had double the risk of advanced prostate cancer.