You Are (Not Exactly) What You Eat
If you’ve ever wondered why a vegetarian who consumes no saturated fat can have a cholesterol level of 240 while an overweight meat lover who lives on cheeseburgers and whole milk clocks in at 160, you’ll be interested in the work of Katherine Tucker, PhD, an epidemiologist at Tufts University’s Friedman School of Nutrition Science and Policy. Tucker is a researcher in the field of nutrigenomics, the study of how our genetic dispositions affect the way our bodies use the nutrients in what we eat. She believes that nutrigenomics researchers will be able to unravel some of the paradoxes that have emerged from major studies, such as why some people need more folate in their diet to process homocysteine, an amino acid that can damage arteries. "Current population-based studies often have conflicting and confusing results regarding specific nutrients and health outcomes," Tucker says. She thinks genetic predisposition, which is not taken into account in large-scale epidemiological studies, will probably explain the perplexing results.
"The nutritional advice we’re giving right now is based on the average person," Tucker says. Nutrigenomics research should make it possible for healthcare providers to give more customized advice in many areas, including weight loss.
Although nutrigenomics is still in its infancy, Tucker expects it to become a major player in the science of aging. "In 10 years," she says, "individuals will go to their doctors, have their genetics analyzed and be told, for example, that fish oil can help reduce their risk of heart disease and Alzheimer’s disease" — while that same advice may not be useful to people with a different genotype.
Cleaning Up the Brain
An amazing thing happened when Kim Finley, PhD, managed to maintain a cellular cleanup mechanism in the brains of fruit flies as they aged: They lived longer — by 55 percent, on average. "It was one of the most dramatic life span extensions ever found in flies," says Finley, staff scientist at the Salk Institute for Biological Studies, in La Jolla, California. "Plus, those flies were extremely healthy."
Now Finley wants to know whether the same process will work in humans. If it does, it could have a major impact on the preventive treatment of Alzheimer’s disease and other neuro-degenerative disorders in which an excessive amount of damaged proteins in brain cells contributes to the death of the cells. "What I need to be able to do is see if this is doing the same thing in people, and all indications are that it is," Finley says.
The mechanism Finley kept functioning is called autophagy, the process by which cells remove damaged protein molecules and other "trash" that accumulates as we age. As each birthday goes by, our autophagy likely slows down, and as cellular trash builds up, it damages and kills cells. Finley hopes a drug will be developed that will keep the autophagy process running smoothly. People may not necessarily live longer, as the flies did, she says, but they may experience a slower cognitive decline.
Fighting Cancer from the Inside
The latest mantra of Susan Love, MD, long a warrior against breast cancer, is "Go to the source." In this case, that would be the half dozen or so milk ducts in the nipple. "All breast cancer starts in the lining of these milk ducts," says Love, of the Dr. Susan Love Research Foundation, in Pacific Palisades, California. "It makes sense that if you can get to where it starts, you can prevent it." (A 40-year-old woman has a one in 70 chance of developing breast cancer; a 50-year-old woman has a one in 40 chance, according to the American Cancer Society.) In a new study, Love and her colleagues will look at whether introducing a low dose of chemotherapy into the milk ducts under local anesthesia can destroy precancerous cells or keep them from progressing to invasive cancer (which can spread to the rest of the breast and beyond). If intraductal chemotherapy works, it may spare women disfiguring surgery and radiation. "Rather than doing preventive mastectomies," Love says, "wouldn’t it be great if we could just squirt something down the duct and clean it out?"