FROM THE DIRECTOR
Balz Frei, Ph.D.
It’s been a year since we moved into our new home, the Linus Pauling Science Center at Oregon State University. We are very pleased to work in such modern, state-of-the-art facilities, which have transformed the Institute and elevated it to new heights. The open laboratories and shared core facilities; the bright, well-designed offices and conference rooms; and the informal meeting spaces throughout the building have created a stimulating intellectual environment and facilitated new interactions and collaborations. This has resulted in new collaborative research projects, joint publications, and multi-investigator grant applications.
It feels like we have finally arrived—we have achieved the vision we had when the Institute moved here to OSU from Palo Alto many years ago. This vision was to have a state-of-the-art research and teaching facility where top-notch faculty and their students and post-docs, supported by an efficient administrative team, work together to discover new ways of solving some of the most pressing health-care problems facing our nation. We all share a conviction that prevention is the medicine of the 21st century, and that nutrition, micronutrients, and lifestyle are key to improving public health and getting the spiraling health-care costs under control.
The overarching goal of our work in the Institute is to help people extend their healthy lifespan (healthspan)—how we can stay healthy and vital up to an old age. Health in this context is not just defined as the absence of chronic disease but also the absence of infirmity and deficits of daily living as we get older, as well as “a state of complete physical, mental, and social well-being,” as the World Health Organization defines it. For example, research in our Healthy Aging Program is discovering new “age-essential micronutrients”—compounds like carnitine, lipoic acid, and coenzyme Q that we synthesize in our body and obtain from our diet in sufficient amounts when we are young but have a hard time synthesizing and absorbing as we get older. To overcome these limitations and assure optimum functioning of all cells and tissues, we may have to take supplements of these compounds.
Age also may increase the need for certain vitamins and nutritionally essential minerals. For example, older adults often do not get enough vitamin C from their diet and may have lower intestinal absorption of vitamin C than younger people. The capacity of our skin to synthesize vitamin D upon sun exposure also declines with age. Since both vitamins C and D are important for good immune function, inadequate levels in our bodies may lead to increased susceptibility to infectious diseases in older adults. An efficient immune system also is important for surveillance and elimination of malignant cells, keeping cancer at bay.
Another interesting connection exists between vitamin C and carnitine in that vitamin C is required for two enzymes in the biosynthetic pathway of carnitine. Carnitine is required for the transport of fat into mitochondria where it is oxidized (“burned”), releasing energy required for normal metabolism and good functioning of our body. Hence, inadequate intake of vitamin C may lead to lack of energy in older adults, and vitamin C or carnitine supplementation may help overcome this deficit.
Two recent studies related to the topic of healthspan caught my eye. The first one, conducted at the Cooper Clinic in Dallas, Texas, investigated the relationship between “cardiorespiratory fitness” in middle-aged adults and the development of chronic diseases later in life. Treadmill time was measured in over 18,000 healthy men and women when they were at a median age of 49. After a median time of 29 years, the prevalence of eight chronic conditions in these individuals was assessed: congestive heart failure, ischemic heart disease, stroke, type II diabetes, chronic obstructive pulmonary disease, chronic kidney disease, Alzheimer’s disease, and cancer of the colon or lung, the two most common causes of cancer deaths in the U.S.
Not surprisingly, the investigators found that individuals with higher blood pressure, serum total cholesterol, body mass index, serum glucose, and smoking prevalence had a higher risk of developing these chronic conditions. However, individuals with the highest level of midlife fitness had the lowest incidence of chronic conditions and spent the last five years of their lives in much better health than people with the lowest level of fitness at midlife. The authors concluded that “higher midlife fitness may be associated with the compression of morbidity in older age”—in other words, while lifespan was not extended, healthspan was.
The second study was conducted at the National Institute on Aging (NIA) and investigated the effect of caloric restriction on health and survival in rhesus monkeys. Restricting caloric intake by 10-40% has been reported previously to extend lifespan in worms, flies, rats, and mice. But whether the same approach also can extend lifespan in primates, including humans, is not clear. In this study at NIA, monkeys of different ages were fed a diet restricted by 30% in calories and compared to a non-restricted control group. Interestingly, the investigators found that caloric restriction did not extend lifespan. This result is different from that of another study conducted at the Wisconsin National Primate Research Center (WNPRC) that found a significant extension of lifespan in calorically restricted rhesus monkeys. Nevertheless, the NIA study, like the WNPRC study, found a lower incidence of cancer and diabetes in those animals that were calorically restricted. Measures of “metabolic health and overall function” were also improved, including lower body weight; lower serum triglyceride, total cholesterol, and glucose levels; and less oxidative stress.
In trying to explain the difference in results regarding lifespan extension between the NIA and WNPRC studies, the NIA scientists noted that the diets fed to the two groups of monkeys differed significantly. The WNPRC monkeys received a diet containing 28% sucrose, compared to only 4% in the diet given to the monkeys at NIA. The NIA diet, which has a natural ingredient base, also contains fish oil and phytochemicals, including flavonoids, and protein derived from wheat, corn, soybean, fish, and alfalfa. In contrast, the WNPRC diet is a “purified” diet with no added fish oil or phytochemicals, and protein from a single source called lactalbumin. Hence, the authors suggested that the WNPRC monkeys on caloric restriction lived longer than their non-restricted counterparts because they got less of a bad diet that caused the ad libitum-fed (without restraint) control monkeys to die prematurely. In contrast, the NIA monkeys got a healthier diet and lived longer, and under these circumstances, caloric restriction did not extend lifespan. Dr. Viviana Perez further discusses caloric restriction in her interview in this newsletter.
Bottom line: maintaining a healthy body weight is important, but you don’t have to starve yourself to get there. A much better way is to be physically active and maintain a high level of fitness throughout life. And diet composition matters for good health. None of this will help you live longer (except for the morbidly obese), but chances are you will live a much healthier and more enjoyable, active life up to an old age.
Last updated November 2012