Life Extension Magazine February 2010
Activate Your Longevity Genes: Five Natural Compounds Simulate Caloric Restriction
By Julius Goepp, MD
The most scientifically validated way to extend life span—from single-celled organisms to mammals—is caloric restriction.1 This technique has been shown to boost life span by nearly 100% in some species.2
Reducing the number of ingested calories—while maintaining healthy intake of essential nutrients—triggers a cascade of anti-aging mechanisms in the body. More than 70 years of research have established its life-extending power.3
Modern science has only recently begun to unravel the mystery behind how calorie restriction so radically extends life span. At its core lies favorable alterations in gene expression—one of the body’s adaptive responses to reduced calorie intake. By activating certain genes and disabling others, caloric restriction dramatically slows aging.
This retardation of aging delays the onset of degenerative disease while improving biomarkers of youth, ranging from metabolic rate and insulin sensitivity to cardiac health and cognitive function.4
By the same token, the consequences of caloric overconsumption are equally profound. Every excess calorie brings you one step closer to age-related illness and death.
This is true at any stage of life, whether you’re lean or overweight, regardless of your health or nutritional status.5-7
Eating more than your body needs (excessive energy intake) can load the blood with triglycerides, glucose, homocysteine, and pro-inflammatory chemicals. The results are accelerated aging processes, prompting deterioration across multiple biomarkers of health.8
Most humans find it difficult to submit to a sufficiently rigorous dietary regimen, leaving the benefits of calorie restriction tantalizingly out of reach. Until now!
In this article you will discover the most compelling evidence to date on the effects of caloric restriction. In a milestone 20-year study of Rhesus monkeys—our close genetic relatives—a modestly restricted diet resulted in a three-fold reduction in the risk of age-related disease!9
You will also learn about five natural compounds that favorably modulate gene expression to support a more youthful health profile. These “caloric restriction mimics” simulate many of the beneficial effects of caloric restriction through multiple pathways.
Aging individuals may now enjoy some of the youth-promoting, disease-fighting mechanisms of caloric restriction—without strict dietary measures.
A Milestone in Longevity Research
In 1989, a group of anti-aging researchers launched what would prove to be the most comprehensive study of caloric restriction (CR) to date.10 Rhesus monkeys were chosen as subjects because they exhibit biological and aging characteristics strikingly similar to humans. The results, published in 2009 in the prestigious journal Science,9 provide compelling evidence of CR’s age-delaying, disease-fighting power.
The monkeys were split into two groups. Half were allowed to eat naturally, without restraint; the other half subsisted on a nutrient-replete diet 30% lower in total calories than they would normally consume. After 20 years, 37% of controls had died of age-related causes, as opposed to just 13% in the calorie-restricted group. In other words, caloric restriction cut degenerative disease risk by a factor of three.9
This study’s findings are even more tantalizing when one sees that it did not require severe lowering of calorie intake to produce these striking results. Americans typically consume 100% more calories than they need. It only required a calorie reduction of 30% to achieve the remarkable benefits in this study.
The Rhesus monkey study also conclusively demonstrated caloric restriction’s protective power. Over the course of 20 years, virtually all measured biomarkers of health were superior in the CR group.9
These findings have profound implications for humans. Rhesus monkeys are as vulnerable to chronic, age-related disease as we are. They lose their strength over time. Many become obese, fall prey to metabolic syndrome, and succumb to diabetes. They develop cardiovascular disease and cancer. And like aging humans, their brains shrink as they get older.
Yet among the calorie-restricted group, incidence of cardiovascular disease was half the rate ofcontrols. Not one member exhibited any symptoms of impaired glucose control or diabetes, whereas 40% of monkeys who ate as much as they wanted had become diabetic or pre-diabetic.9
Calorie-restricted monkeys lost fat weight, but did not sustain loss of muscle mass observed in the control group. CR also inhibited reduction in brain volume, especially in areas governing cognitive and motor function.9
The robust health of the CR group compared to controls is clearly evident in photographs of the monkeys from the control and CR groups.9 (See figure 1 below.)
Benefits of Calorie Restriction in Humans
All available data indicate that calorie restriction also slows aging and reduces the risk of killer diseases in humans as well. Individuals who impose a 20% reduction in their calorie consumption for 2-6 years lose fat weight and show significant improvement in their markers of aging, including blood pressure, cholesterol levels, and glucose control.11
Even brief periods of caloric restriction can temporarily improve core body temperature and insulin sensitivity, which happen to be markers of longevity.11,12 In clinical studies, short intervals of caloric restriction have reduced systemic inflammation—an underlying factor of so many chronic, degenerative diseases.
More youthful heart muscle performance13 has also been observed—caloric restriction appears to increase the number of vital energy-producing mitochondria in heart and skeletal muscle, reducing the oxidative damage that accelerates aging.14-16
No other intervention documented in the scientific literature can compete with caloric restriction as a candidate for slowing aging and supporting youthful health in humans.
It is regrettable that most aging individuals don’t lower calorie intake by the 20-30% reduction required to reap the benefits of caloric restriction, as it can dramatically lower disease risk and add years to their lives.
Caloric Restriction “Mimics” and Gene Expression
The problem many people have in sufficiently reducing their calorie intake has led to a novel scientific solution.
Researchers have identified a select group of nutrients that trigger many of the same underlying mechanisms of action as caloric restriction. Among the most promising of these caloric restriction mimics and enhancers are resveratrol, pterostilbene, quercetin, and grape seed extract, along with black tea extract. These nutraceuticals have been shown to generate many of the same effects in the body as caloric restriction, without significant dietary modification. In particular, they “mimic” caloric restriction’s favorable impact on genes that influence the aging process.
Genes have the capacity to directly affect life span by regulating a broad spectrum of aging factors, from inflammation and metabolic function to immune response. Calorie restriction exerts a beneficial effect on the activity of gene expression, supporting healthy cellular function through numerous physiological pathways. This includes:
Compounds that mimic caloric restriction bring about favorable changes in gene expression and improve the primary biomarkers of aging.
Controlling Nuclear Factor-Kappa B
Calorie restriction sharply limits expression of nuclear factor-kappa B (NF-kB). In the cells, NF-kB is a critical gene regulator that governs response to pro-inflammatory cytokines, free radicals, cholesterol levels, immune function, and cancer prevention.17-24
The nutrients that mimic caloric restriction also act to stabilize NF-kB regulation and help combat the age-related conditions associated with unfavorable NF-kB activity.
Resveratrol activates sirtuins,25 a powerful family of “information regulator” proteins that inhibit NF-kB, reducing inflammation throughout the body, such as that caused by second-hand cigarette smoke.24 Resveratrol also prevents inflammatory mast cells from releasing the histamines that trigger asthma and allergic reactions.26
Resveratrol radically decreases production of the adhesion molecules that attract inflammatory cells to vascular walls, one of the principal mechanisms of atherosclerosis.27,28 Adhesion molecules also permit cancer cells to invade tissue and metastasize. Resveratrol’s influence over NF-kB has also enhanced beneficial UV-induced programmed cell death (apoptosis) in skin cancer cells.29
Found in blueberries, pterostilbene is a polyphenol closely related to resveratrol.30 It limits NF-kB activity through multiple complementary mechanisms.31 In vitro, pterostilbene suppresses invasive tumor activity and enhances therapeutic destruction of cancer cells.32,33
Quercetin’s ability to protect against chronic inflammatory conditions such as asthma, inflammatory bowel disease, and arthritis is due in part to its capacity for NF-kB inhibition.34,35
Grape seed extract also disrupts cellular inflammation signaling by blocking NF-kB.36 Its effect on pro-inflammatory cytokine production in fat cells may even help combat obesity and type 2 diabetes.37
Black tea extract’s influence on NF-kB activity has been shown to specifically protect cells from damage associated with inflammation,38 cancer,39,40 Parkinson’s disease,41 and stroke.42
Suppressing Inflammatory Cytokines
Caloric restriction inhibits expression of genes that produce inflammatory cytokines—such as interleukins and tumor necrosis factor (TNF), as well as cyclooxygenase-2 (COX-2)—that are powerfully implicated in the onset of cancer, atherosclerosis, and chronic inflammation.43-46
Resveratrol and pterostilbene block the release of a host of inflammatory cytokines and enzymes found throughout the body—particularly tissues and organs stressed by environmental factors, infection, or trauma.22,47,48 Pterostilbene powerfully suppresses the expression of inflammatory COX-2,31,49 helping lower the risk of cancer as well as a host of inflammatory diseases.50,51
Quercetin inhibits the COX-2 enzyme involved in early-stage colon cancer, and suppresses numerous cytokines involved in allergies and autoimmune disorders.34,35,53
Grape seed extract specifically prevents fatty tissue from releasing inflammatory cytokines and adipokines that would otherwise provoke insulin resistance and atherosclerosis associated with metabolic syndrome.37 By downregulating reactive cytokines, grape seed extract has been shown in animals to protect organs from ischemia-reperfusion damage (injury caused by the return of blood flow after a period of restriction).54
Black tea extract reduces levels of STAT-1, a protein which “tells” the cell nucleus to activate genes that produce inflammatory cytokines.55