In the fight against aging, most of us need all the help we can get. The following are the five theories anti-aging experts attribute to its causes, amplification and prevention.

Inflammation
The activation of the immune system—due to an infection, allergen or toxin—leads to internal inflammation at the cellular level. Poor nutrition, too little sleep, and radiation are common culprits of low-grade inflammation, which has been linked to arthritis, cancer, Alzheimer’s disease and heart disease.

Lifestyle
What we eat (too much sugar, fat and sodium), drink (too much soda, juice, etc.), do (get overstressed, work too much), don't do (exercise or sleep enough), and what we expose ourselves to can speed up the aging process and the development of chronic diseases.

Hormones
Levels of estrogen, progesterone, testosterone, DHEA, thyroid and/or human growth hormone drop as we age. But by increasing these all-important biochemicals, it may be possible to improve health and forestall the aging process. A controversial approach, hormone therapy requires oversight by an experienced physician.

Antioxidants
Call it the "rusting" theory. As we get older, we're subject to oxidative stress, the byproduct of free-radical damage, a natural process in which unstable molecules disrupt cell and tissue functioning. Antioxidants such as vitamins A, C, and E, glutathione and alpha lipoic acid can help protect cells.

Detoxification
When the body can't rid itself of toxins, including high amounts of sugar, trans fat, mercury and chemicals we ingest from our food, its equilibrium is impaired, leading to fatigue, poor skin, heart disease, cancer and more. Detoxification and inflammation are closely linked.
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