Alanine (Ala, L-alanine)

One of the simplest AMINO ACIDS used to build PROTEINS. Alanine is readily formed in the body from PYRUVIC ACID, a direct product of GLUCOSE utilization; hence, it is classified as a non-dietary, essential amino acid. In addition to serving as a protein building block, alanine plays an important role in transporting the toxic waste product, AMMONIA, out of muscle. Ammonia is produced when muscle cells break down amino acids for energy. Cells couple ammonia with a simple acid called pyruvic acid to form alanine, which is then released into the bloodstream.
The LIVER next absorbs alanine and removes ammonia, which it rapidly converts to UREA, the ultimate nitrogenous waste of the body.
The liver converts pyruvic acid back to glucose, which is released into the bloodstream. Blood glucose is taken up by the muscle, where it is broken down to pyruvic acid, which is then ready to accept ammonia and thus completes the cycle.

Airline Meals and Nutrition

Over the years, airlines have revised the meals they serve in order to meet consumer expectations for more healthful choices. Changes include more chicken and less beef and fewer saturated fats, like coconut and palm oil.
On noncharter flights passengers can choose from up to a dozen special dietary meals. The requests must be made at least 18 hours ahead of the scheduled flight. Religious meals include kosher, Hindu, and Muslim. For medical conditions, bland, diabetic, GLUTEN-free, low-CALORIE, low-CARBOHYDRATE, low- CHOLESTEROL, low-fat, and low-SODIUM meals may be offered. Other options include a FRUIT plate, SEAFOOD, strict VEGETARIAN, ovolactovegetarian, and infant, toddler, and child meals. First-class meals follow the same nutritional standards.
Passengers on long flights, especially those who have been diagnosed as having phlebitis, inflammation of the VEINS in the leg, or who have a history of heart disease or stroke are considered at high risk of developing deep-vein thrombosis (DVT). A person suffering from deep-vein thrombosis has one or more blood clots in the body’s deep veins, often those in the legs. Because constant air circulation in planes promotes DEHYDRATION, and this, coupled with prolonged sitting, increases the risk of DVT in even healthy people, passengers should drink plenty of fluids, including water and JUICE, and avoid ALCOHOL, COFFEE, and TEA on long flights. About 4 percent to 5 percent of high-risk patients may suffer DVT on flights of 10 hours or more. A brown-bag, carry-on meal is always an option for those with special dietary needs or with food sensitivities.

Nutrients for AIDS Patients

There is no cure for AIDS; however, several nutrients, food-related materials, and ENZYME preparations boost the immune system and may offer protection against the risk of CANCER and infection in some individuals with AIDS. Trace Nutrients ZINC deficiency is common in patients with AIDS and may indicate trace mineral malnutrition or malabsorption. Zinc plays an important role in maintaining the immune system. Zinc inhibits an enzyme needed for HIV production.
SELENIUM deficiency may be part of the malnutrition seen in AIDS patients. It is a COFACTOR for enzymes that serve as ANTIOXIDANTS. Selenium helps protect against liver and colon cancer in experimental animals, and clinical studies of the effects of selenium supplementation on cancer prevention are being carried out. Other vitamins and minerals, such as VITAMIN A, FOLIC ACID, VITAMIN B12, and POTASSIUM, may be deficient in some AIDS patients.
Enzymes Megadoses of a variety of enzymes, including SUPEROXIDE DISMUTASE, are being used as antioxidants. There is no clear evidence that their use diminishes or prevents symptoms.
Antioxidants Evidence suggests that HIV infected patients have lower levels of antioxidants, ncluding VITAMIN C, CAROTENOIDS, COENZYME Q, LUTATHIONE, and selenium. Such oxidative stress can promote HIV replication and decrease immunity. Antioxidant nutrients may lower the risk of cancer in the general population, and the same may be true for HIV-infected patients. BETACAROTENE and carotenoids may lower the risk of many cancers, including those of the lung, bladder, stomach, esophagus, and prostate. Beta-carotene can increase the numbers of T-helper cells. Significantly, the standard American diet is deficient in beta-carotene. Vitamin C boosts immunity, helps protect against viral and bacterial infections, and may decrease the risk of stomach, esophageal, and cervical cancer. It increases blood antibody levels and supports the function of the THYMUS GLAND and lymphocytes. Furthermore, vitamin C supports healthy connective tissue and assists in wound healing. FLAVONOIDS are associated with vitamin C in plants and enhance vitamin C therapy. Many flavonoids function as antioxidants and several types may stimulate the immune system. GLUTATHIONE supports the immune system and functions as a major antioxidant. N-acetylcysteine, a derivative of the sulfur amino acid CYSTEINE, can enhance glutathione levels.
Egg Lipids Mixtures of LECITHIN and other fatty materials from eggs have been used with some positive results in small clinical studies. Although there is a lack of strong evidence of its effectiveness, these mixtures are still being used. They are apparently nontoxic, though long-term effects are unknown.
Herbs Several herbs, such as GOLDENSEAL (Hydrastis canadensis), have been shown to enhance several aspects of immune function. The most active component of goldenseal is berberine, a broad-spectrum antimicrobial agent effective in treating the severe DIARRHEA that is typically seen in AIDS patients. Herbal treatment based on Chinese medicine is also being studied. Certain formulations inhibit viruses and boost the immune system. Some research suggests garlic may enhance immunity and help combat opportunistic organisms associated with AIDS, including Candida albicans, cryptococcus, herpes virus, and mycobacteria.

Antioxidants for Seniors

Several nutrients seem to protect the body throughout life against damage by free radicals, highly reactive forms of oxygen that can attack cells. Trace minerals like copper, SELENIUM, and zinc, as well as vitamins C and E plus BETACAROTENE, function as antioxidants. Together with vitamin A they also keep the immune system balanced. The immune system protects the body against bacterial and viral diseases and defends against cancer.
Other ingredients in foods, especially fruits and vegetables, act as ANTIOXIDANTS. They strengthen the body’s defenses and protect against cancer. These include FLAVONOIDS, PHYTOESTROGENS (ISOFLAVONES), and ISOTHIOCYANATES. Many more remain to be identified. From hundreds of studies, it is clear that diets that provide ample fruits, legumes, and vegetables protect against many of the degenerative diseases that commonly occur with aging. As an example, middle-aged men and women who eat plenty of fruits and vegetables are significantly less likely to experience cardiovascular disease and strokes.
More research is required to determine the optimal intake of anti-aging nutrients. Foods with antiaging nutrients include orange vegetables (CARROTS, SQUASH) and dark green leafy vegetable (CHARD, KALE, SPINACH) for vitamin A and betacarotene.
Fresh fruit like ORANGES, frozen citrus juices, and BROCCOLI provide vitamin C. VEGETABLE
OIL, WHEAT germ, and nuts supply vitamin E, while whole GRAINS, SEAFOOD, CABBAGE, ONIONS, and GARLIC provide selenium

Vitamins for Seniors

Research suggests there may be increased vitamin needs in elderly people; however, no definite proof that vitamin supplements increase the life span has been offered. Many elderly Americans obtain less than 50 percent of the Recommended Dietary Allowance of VITAMIN antihypertensive drugs interfere with absorption of this vitamin. Folic acid and vitamin B12 are less well absorbed in elderly persons, and the RDAs should be higher. Inadequate diet and decreased uptake of fat-soluble vitamins probably account for the increased need for VITAMIN A and VITAMIN E with aging, and extra vitamin E may boost immunity, thus helping elderly persons resist disease. Vitamin E has also shown promise in slowing decline in mental functioning in the elderly. One study showed that people who took high amounts of vitamin E had a 70 percent reduction in the risk of developing Alzheimer’s disease. In another study researchers followed more than 2,800 people over the age of 65 for three years. Those participants who had the highest amount of vitamin E consumption showed the slowest decline in mental alertness. Vitamin D requirements may increase during aging because the skin gradually loses its ability to manufacture the vitamin. Patients with hip fractures may be deficient in vitamin D. Another problematic nutrient for elderly people is VITAMIN C, a versatile antioxidant. Consumption may be low with diets relying on processed, overcooked foods and lacking adequate fruits and vegetables. Vitamin C may protect against cataracts and atherosclerosis.
The RDA for RIBOFLAVIN is believed to be too low for elderly people. Geriatric outpatients can exhibit low-THIAMIN levels and evidence suggests that RDA of this critical nutrient is greater for older people than for middle-aged individuals.

Minerals for Seniors

Diminished digestion and ABSORPTION can lead to deficiencies of MAGNESIUM, IRON,
ZINC, COPPER, and CALCIUM. Older persons probably need more than the current calcium RDA of 800 mg because the ability of the intestine to absorb adequate calcium declines progressively with age. The common experience is that the bodies of elderly women and men remove calcium from their bones to meet their calcium needs. Supplementation with calcium and VITAMIN D, or calcium with low-dose ESTROGEN for post-menopausal women, seems to be more effective in slowing bone losses than supplementation with calcium alone. Normally, iron stores increase throughout adult life in men and in women after menopause. However, blood loss due to chronic ASPIRIN use and bleeding ulcers can cause iron deficiency; 5 percent of elderly men are iron deficient in the United States. CHROMIUM stores in the body decline steadily with age and this may contribute to the decline in the regulation of blood sugar. Chromium assists in insulin action and helps blood sugar regulation in some diabetics. Low chromium is correlated with elevated blood cholesterol levels.

Nutrient Needs During Aging

Elderly persons are prone to MALNUTRITION for several reasons. They are more likely to eat alone and so take less interest in meal preparation, and they are more often disabled and immobile. Thus, they are less likely to eat properly. More than 30 percent of homebound older individuals may have difficulty in preparing their own meals. Low-fiber, high-carbohydrate meals typify the diets of many elderly persons. They use more LAXATIVES and medications for long periods. Furthermore, many elderly persons have periodontal disease and poor teeth. Their senses of smell, taste, and sight decline, making eating less appealing, and STOMACH ACID production gradually drops, decreasing nutrient uptake even with an adequate diet.
Evidence indicates that superior nutrition may prevent unnecessary illness and disability from shortening a productive life. Therefore, experts recommend the following health decisions:

• Avoiding excess calories and ALCOHOL. Surplus calories regardless of their source are converted to fat. Excessive body fat contributes to the risk of heart disease, hypertension, and some forms of cancer. Besides carrying a risk of addiction, excessive alcohol can damage the liver, pancreas, and brain, in addition to depleting the body of nutrients.
• Medical testing of stomach acid production. Low stomach acid production sets the stage for inadequate digestion of nutrients.
• Making informed choices regarding nutritional supplements. They can affect the quality of health of those who are nutrient deficient, though eating wisely.
• Choosing a diet based on DIETARY GUIDELINES FOR AMERICANS as a foundation. A BALANCED DIET, one that provides adequate amounts of all nutrients and FIBER from varied, minimally processed foods without excessive calories and FAT, is of paramount importance.