Biology 103
2000 Second Web Report
ON Serendip

Accepting and Adapting: Antioxidants and Aging

Naomi Lim

The maintenance of youth or youthfulness, in both past and present times, has been a goal aspired to by many. Indeed, just as Ponce de Leon searched for the fountain of youth in the 16th century, pharmaceutical companies and the food industry alike account for this seemingly improbable quest today, albeit in the derivation of antioxidant pills or supplements and "functional foods". However, while Ponce de Leon's never-ending search for the mythical Fountain of Youth proved to be fruitless, the current research on anti-aging remedies, specifically antioxidants, seems to be progressing and also bifurcating into uncertain dimensions. As the research and development in this field expands, numerous questions are raised as to how aging is perceived, as well as how it should be approached, leading to larger social and moral/ethical implications concerning the claims that corporations make.

Scientific observation has shown that aging causes reduced ability to use calories from food, reduced function of hormones, depressed enzyme function, and reduced ability to fight disease (4). The most prevalent explanation for this has been the oxidative theory, otherwise known as the free radical theory of aging, which postulates that aging results from an accumulation of changes caused by reactions in the body initiated by highly reactive molecules known as free radicals (8).

When oxygen is burned or metabolized by the body, cells produce by-products called "free radicals" (2). Free radicals are atoms or groups of atoms with an odd (unpaired) number of electrons, which makes them highly reactive (5) and unstable. By nature, such molecules are always looking for a partner to bond with (6) and generally attract the nearest stable molecule "stealing" its electron (7). When the attracted molecule loses its electron, it also becomes a free radical, beginning a chain reaction and usually resulting in the disruption of a living cell (7). Free radicals promote beneficial oxidation that produces energy and kills bacterial invaders (5), but in excess through accumulation, they can disturb cell structure, resulting in cellular damage in protein, fat and DNA molecules (4). This is believed to contribute to aging, as well as various other health problems, because the human body's functions depend on these molecules.

To try to resist free radical activity, scientists have been studying the effects of increasing antioxidant levels in individuals through diet and dietary supplements (2). It is believed that the body uses food components, such as Vitamin C, Vitamin E, and beta-carotene, as well as a variety of enzymes to destroy free radicals by beneficially combining and inactivating them and preventing cellular damage. Antioxidants such as these neutralize free radicals by donating one of their own electrons, ending the "electron-stealing" reaction (7). They do not become free radicals in the process because they remain stable. Instead, they act as "scavengers", helping to prevent cell and tissue damage that could lead to cellular damage and disease (7).

Recent studies seem promising, although there are still many uncertainties as to whether the effects can be specifically traced to certain nutrients. Christiaan Leeuwenburgh, a professor in the University of Florida's College of Health and Human Performance, in a study done with Heinecke, Holloszy, and Hansen of the Washington University School of Medicine, found that anti-oxidant intervention slowed down basal skeletal muscle oxidation, a type of tissue and muscle loss that occurs with aging, in rats (1). Leeuwenburgh divided the rats into two groups, one of which was given an anti-oxidant diet of Vitamins C and E, and beta carotene. After 21 months, the rate of muscle oxidation for rats in the anti-oxidant group was 50% lower than the rate for the rats in the control group (1). In addition, some rats, which were not fed anti-oxidants but exercised regularly, showed a decrease in muscle oxidation. However, the combined effects of exercise and anti-oxidants did not show a significantly lower level of muscle oxidation.

While some antioxidants, such as Vitamins C and E are made or obtained by diet, others, such as the enzyme SOD (superoxide dismutase) are produced in the body. SOD supposedly aids in digestion and metabolism by helping to diffuse vitamins and minerals into the blood stream to be absorbed by the body. In his studies, Dr. Richard Cutler, a biophysicist at the National Institute of Aging, found that the animals and men with the longest life spans had the highest levels of SOD. As for SOD supplements, some studies seem to show that SOD pills have no effect on the body (14). This is significant because it is a highly marketed and consumed supplement.

Many experts are not yet convinced that there is enough data for health claims on foods or dietary supplements (2) because questions remain on "...which antioxidants may prevent what conditions, their mechanisms of action, optimum levels of intake and their long term effects" (2). For example, although Vitamins C and E are rich in anti-oxidants, many experts think that the best way to get these vitamins is by eating fruits and vegetables rather than by taking vitamin pills, because it is not known which factors are responsible for the beneficial effects they may possess (5). In addition to applications in issues of general health, such claims are also implicated and especially pertinent to aging and hence, age-related diseases because "An avalanche of research data suggests that high intakes of antioxidant-rich fruits, vegetables and supplements lowers the risk of old-age diseases" (15).

The U.S. Food and Drug Administration, which has refused to endorse the health claims of beta-carotene or vitamin E supplements, has found that consuming a diet rich in fruits and vegetables reduces cancer risk (10). Such a diet seems to be more effective in preventing cancer than supplements because each fruit and vegetable has hundreds of constituents. The protection from disease is likely a result of a combination rather than any single factor. The extensive research on the effects of these antioxidants on both aging and disease, indicates, that, like diseases, some aspects of aging can be prevented. Aging, hence, is considered a disease in certain aspects because it needs to be fought off, and consequently there is a need to search for a "cure".

Demographical facts seem to be driving the anti-aging medicine trend. In 1999 1 in 8 Americans were age 65 or older. By 2010, it is estimated that that number will rise to 1 in 5 (13). This trend is also prevalent in advertisements for foods that display the changing concepts of what constitutes "healthy aging". Having started in the 1980s with oat bran, it seems that there is no foreseeable end to the onslaught of seemingly weekly announcements about foods that battle heart disease, fight cancer, and even boost the immune system - all degenerative conditions associated with aging. "Functional foods" are a $100 billion dollar-a-year industry. Even candy companies like Mars, Inc. are funding research to prove that chocolate is healthy. "Companies are more than happy to promote the healthiness of their products, even if scientists don't understand how they work" (11). This, it seems, is the large scale problem behind research into anti-aging and antioxidants.

Thus, stricter guidelines are necessary, to keep companies from making far-reaching claims without proven results. This will prove to be difficult in the highly competitive world of the food industry, as marketing is well ahead of science (12). Because many of the products out on the market are unfounded in their claims, experts urge Americans to eat five to nine servings of fruits and vegetables daily (10).

However, aging may also be influenced by the amount of food consumed, as well. In laboratory animals, the only known way to prolong life is by food restriction by 5 to 40% of what they would normally eat if given free access to food (4). This is because food restriction reduces free radical production. Moreover, at higher concentrations, Vitamin C and beta-carotene are pro-oxidants, and therefore, harmful (3). It is important, then, to consider the amount and kinds of foods consumed. To further complicate matters, although most oxygen free radicals are created by the body as the cells produce energy, they also come from smoking, radiation, sunlight, and other factors in the environment (9). Thus, rather than looking at specific foods or enzymes or antioxidants as a cure, it seems necessary to examine one's way of living as a whole to see whether or not one is getting the proper amount and kinds of food, as well as the proper type and amount of exercise.

While searching for the specifics may answer some questions, more questions are inevitably raised. There is no way to know for sure, which is why research in this field, while beneficial, is also dangerous. Living in a capitalistic society, which is focused on making money, there is a need also to examine who is doing this research and how they are promoting their products. Offering easy solutions to a society that is more than willing to accept and buy into the claims that products make, is a moral/ethical issue that deserves attention, especially when considered in the context of big pharmaceutical and food corporations. As in all research, there are always other variables and implications. Moreover, in our continual need to differentiate between what is really aging and what is a result of own deconditioning, there is a need to accept and adapt to the aging process, rather than fighting it.

WWW Sources

1) Antioxidants & Aging Process , article on MGH Neurology Homepage

2)Antioxidants: Antidote to Aging?, on IFIC homepage

3) Antioxidants and Free Radicals , article on riceinfo homepage

4) Vitamins and Minerals, Free Radicals and Aging , article on GFHNRC homepage

5) Antioxidants and Other Phytochemicals , on Quackwatch homepage

6) Free-Radicals, Anti-Oxidants, and Cancer Protection , on Life Span Dynamics homepage

7) Understanding Antioxidants , on Health Check Systems homepage

8) Oxygen Free Radicals and Aging Part I , on Intelegen homepage

9) Anti Aging - Antioxidants - Science or Science Fiction?, on Pioneer Thinking homepage

10) Using Antioxidants: Read the Road Signs and Yield to Caution , article on MD Anderson homepage

11) Researchers: Marketing getting in way of science , article on NASW homepage

12) Healthy Aging or Anti-Aging? Diverse Philosophies Emerge , article on Phys Sports Med homepage

13) The Antioxidant Frontier: The Pioneers, Discoveries and the Struggle to be Heard , article on HSR magazine homepage

14) Information Sheet: Barley Juice and Anti-aging , on Nutrition Lifestyles homepage

15) Aging Gracefully with Antioxidants , article on Exchange homepage

[an error occurred while processing this directive]