Foods are the raw material that provide energy for the 60 trillion cells that make up the human body. Each cell is a miniuniverse and the integrity of billions of its chemical reactions that take place every minute depends a great deal on food and specifically the kinds of food that are consumed. Substances in food have an influence on nearly every health condition. They can act as sedatives, tranquilizers, analgesics, decongestants, diuretics, antidepressants, anti-inflammatories, and anticoagulants. Food compounds can stimulate chemical reactions that produce natural killer cells and interferon to fight
cancer, infections, viruses, and bacteria. They contain components that can regulate cholesterol, lower blood pressure, relieve ulcers, dissolve blood clots, and stimulate the immune system. They have phytoestrogens that help the body regulate the hormone estrogen. Plant estrogens are weaker and more benign as they occupy estrogen receptor sites on the cells and replace the more potent and aggressive hormones that the body makes and the more harmful estrogens circulating in the body from environmental sources.

Elements in food can also cause or exacerbate numerous health conditions including depression,
mental confusion, anxiety, inflamed joints, clogged arteries, a malfunctioning cell metabolism, and they can interfere with nerve impulse transmission and muscle function. For example, hormonelike substances called eicosanoids, which include prostaglandins, leukotrienes, and thromboxanes, that control blood clotting and inflammation and affect autoimmune disorders, are made from fatty acids. Two kinds of eicosanoids are omega-6 and omega-3. Omega-6s are the fatty acids from saturated fats found in meats and dairy products, transfats like margarine, and polyunsaturated fats used in salads and cooking and present in processed foods. These particular fatty acids produce eicosanoids that are inflammatory. They aggravate certain diseases like asthma and arthritis, affect the stickiness of blood
platelets forming blood clots, and accelerate the proliferation of cells, a factor in cancer. They are an influence in illness such as diabetes, rheumatoid arthritis, multiple sclerosis, psoriasis, high blood pressure, migraines, and atherosclerosis.

On the other hand, omega-3s found in fatty fish and some plants produce eicosanoids that reduce inflammation, relax smooth muscle of the blood vessels, and prevent blood platelets from clumping together. The body needs both kinds of fatty acids for various body processes including injury repair, cell growth, proper immune response, and blood clotting. What is important is that the ratio of omega-6s be less than omega-3s. Because most diets contain the reverse, eating 1 to 3 ounces of fatty fish daily or the equivalent amount two or three times a week plus reducing omega-6s will help establish a proper balance. Extra virgin olive oil and cold pressed organic canola oil, because of their inherent properties, are the preferable oils to use in salads and cooking.
Substances in food can cause food intolerances or sensitivities in some people. Unlike allergies, intolerances create reactions that are more subtle and delayed. In fact, several hours to days may pass before a reaction is noticed. Headaches, depression, fatigue, irritable bowel syndrome, rheumatoid arthritis, and mental problems are some of the health conditions that can result. The actual intolerance does not involve the blood or immune system and so it may not be detected by conventional allergy tests. It is recommended that a suspected food be eliminated from the diet for one week, then be reintroduced, while monitoring the effects throughout the process.
Organically grown produce and foodstuffs are preferable because pesticides and fungicides are poisonous and are cumulative. The chemicals from a wide range of foods accumulate in the body. Not only can residues remain on the exterior of the plant, but because spraying can be systemic, the chemical is absorbed through the roots and becomes incorporated into the tissues and flesh. In addition, waxes that are often used on selected produce may contain fungicides. One study has shown that organic foods are higher in nutritive value than those grown conventionally.
Getting nutrients from whole foods in a varied diet is preferable to taking supplements as a substitute in maintaining optimal health. There are nutrients and phytochemicals yet to be discovered in foods that likely play a crucial role. Nutrients work synergistically and isolating them can result in a lessening pharmacological effect. For example, foods containing 40 mg of vitamin C and 10 IU of vitamin E neutralize as many free radicals as 500 mg vitamin C and 800 IU vitamin E. The gamma tocopherol, one of a family of tocopherols, scavenges nitrogen oxides, a class of free radicals that damage DNA, but the alphatocopherol, used in supplements, has no effect. Large amounts of alpha can also cause a depletionof gamma in the body. The array of carotenoids are just as important as beta carotene; lycopene, the red color in tomatoes, for instance, has 10 times more antioxidant activity. EPA and DHA, the beneficial components of fish oil, may not be as effective as eating the whole fish.

The internal equilibrium of nutrients in the body can easily be disturbed by arbitrarily ingesting supplements, especially high doses. A deficiency of nutrients has adverse health effects. With adequate amounts of nutrients the body functions properly, but when too much of a nutrient is ingested or if supplements are taken when the body does not need them, certain results can occur including an inhibiting rather than an enhancing effect and causing a deficiency of other nutrients.
 Excess nutrients can remain unmetabolized, accumulate in the body and interfere with the utilization, metabolism, absorption, and activity of other nutrients and physiological functions. Hormonal and glandular supplements are questionable because the long-term effects are not fully understood. For example, supplemental DHEA, an adrenal hormone that declines naturally with age, can increase insulin resistance, cause the growth of unwanted hair, decrease levels of HDL cholesterol, raise the risk of heart attack, and exacerbate some cancers. Melatonin, a brain hormone, can induce depression, aggravate allergies, constrict blood vessels, suppress fertility and sex drive, and cause hypothermia and retinal damage. Glandular are extracts from animal adrenal, pituitary, thymus, and reproductive glands. It is advisable to take these supplements only under the supervision of a physician.

Protein supplements are usually unnecessary except for specific amino acids when diagnosed as deficient. People in general may be eating too much protein. It is not stored in the body and an excess is converted to carbohydrate, a process that taxes the kidneys and that causes a loss of calcium in the urine. Nutritional yeast is a good food source of the B complex vitamins and trace minerals. Wheat germ is a good food source of vitamin E but turns rancid relatively quickly and should be used within a reasonable amount of time and kept refrigerated. Acidophilus in liquid, capsule, or freeze-dried form contains friendly bacteria and can be taken after meals. It is especially necessary for individuals taking antibiotics, which destroy beneficial intestinal organisms.