Although the average life-span has risen dramatically, the questions of why we age and how to continue to increase life expectancy remain. There are many theories of aging, and several biochemical processes that clearly decline over time. Here, we outline the biochemical processes that lead to decline and the nutritional insight that can slow these processes.
5 Theories of Aging
The Wear and Tear Theory
Over time, the cells and organs of the body are worn down by overuse and abuse. Toxins that damage the organs include excess sugar, fat, caffeine and alcohol in the diet; smoking; UV rays from the sun; and other physical and emotional stresses. As we age, the body loses its ability to repair the damage.
The Neuroendocrine Theory
Hormones are essential for repairing and regulating many bodily functions. Hormone levels are high when we are young, but decline as we age, impairing the body’s ability to repair and regulate itself, and decreasing our vitality.
The Genetic Control Theory
Our lifespan is genetically pre-determined. We are all born with a biological clock that ticks away until it goes off at a certain time. This timing is greatly affected by dietary, environmental, and other factors within our control, such as exercise, stress, and obesity.
The Free-Radical Theory
Free radicals caused by smoking, stress, sugar, alcohol, fried food, and poor nutrition damage cell membranes, cause oxidation (“rust”), and create metabolic waste products that interfere with the cells’ ability to reproduce and repair themselves, interfering with our genetic code, and creating mutant cells that lead to cancer and other diseases.
The Mitochondrial Theory
Mitochondria are the energy-producing centers of our cells. They have their own DNA, which is very fragile, and easily damaged by free-radicals. Over time, mitochondria are less able to produce energy for the cells, further accelerating the aging process.
9 Biological Processes that Decline with Aging
Sensory System
All sensory functions – vision, hearing, smell, taste, and touch – decline with age. Deficiencies in vitamins A, thiamine, B6, B12, and folic acid, along with zinc and copper are common in the elderly, and may reduce the sense of taste, in turn leading to reduced food consumption, resulting in malnutrition.
Hormone treatment: DHEA is an all-around anti-aging hormone that protects the nervous system, thereby enhancing the function of all the senses.
Food: Leafy green vegetables, wild salmon, nuts
Supplements: Zinc: 30-45mg, with copper: 3-4.5mg; vitamin A: 10,000mg
Endocrine System
The Endocrine System regulates hormones. People with healthy endocrine systems look and feel good, and can fight off most infections and chronic diseases. Toxins and free radicals cause the endocrine system to wear out, affecting the immune system and causing a decline in reproductive function and the production of growth hormone.
Many age-related symptoms are caused by a gradual decrease in certain hormones.
Hormones that gradually decline with age
- Human Growth Hormone (HGH)
- DHEA
- Melatonin
- Estrogen
- Testosterone Progesterone
- Thyroid hormone (TH)
While hormone replacement therapy (HRT) can also be helpful in “turning back the clock,” nutrition and lifestyle can support hormone production as well as the prevention or slowing of the aging process.
Immune System
Reduced efficiency of the Immune System is a major contributor to the aging process, and can can lead to infection, chronic inflammation and auto-immune disease. The thymus gland is the main organ of the immune system, and can be supported by boosting the endocrine system.
Hormone treatment: DHEA is considered an all-around anti-aging hormone.
Foods: Leafy green vegetables and healthy fats (coconut oil, avocados, olive oil, nuts, seeds)
Supplements: Calcium: 1000-1500mg; L-arginine: 2-3g; ashwaganda: 3-6g
Metabolic System
The body’s ability to turn glucose into energy decreases with age, resulting in loss of lean muscle mass, insulin resistance, and increased body fat, which leads to cardiovascular and metabolic disease.
Hormone treatment: Thyroid hormone (TH) governs metabolism and helps regulate blood sugar.
Foods: Whole grains, green tea, cruciferous vegetables
Supplements: Alpha-lipoic acid (ALA): 20-50mg; biotin: 50-200mcg; iron: 8-14g
Gastrointestinal System
As we age, changes in the intestines cause malabsorption of nutrients, as does decreased HCL, and lowered gastric motility and incontinence may occur. Also, drugs may significantly affect taste and appetite.
Hormone treatment: TH can improve digestion and increase digestive enzymes and stomach acid
Food: Fermented vegetables, bone broth, coconut oil
Supplements: Digestive enzymes; HCL; probiotics
Reproductive System
All sex hormones decrease with age. In women, there is a steep drop in estrogen and progesterone when ovulation stops (menopause), causing changes in many body tissues. Men experience a decline in testosterone that begins around age 30, resulting in andropause, a slow but steady decline of sexual arousal and performance. Osteoporosis and increased heart disease risk increases for both.
Hormone treatment: HRT (hormone replacement therapy) is a combination of estrogen and progesterone given to menopausal women that reduces osteoporosis and risk of death from heart disease and stroke, and improves Alzheimer’s symptoms, memory, and cognitive function. In men, TRT (testosterone replacement therapy) improves libido, increases muscle mass, reduces osteoporosis and risk of heart disease, and may lower LDL cholesterol.
Food: Non-GMO soy foods; yams; eggs
Supplements: Dong quai (for women); chrysin: 1-3g (for men); vitamin E: 800IU
Nervous System
The Nervous System is especially vulnerable to age-related decline because nerve cells are less able to regenerate. The myelin sheaths that protect nerves deteriorate, causing decreased sensory function (especially sight and hearing but also taste and smell), muscle strength and coordination; changes in posture and gait; and slower reflexes.
Hormone treatment: DHEA stimulates nerve growth and enhances neurotransmitter function.
Food: Wild salmon, leafy green vegetables, sea vegetables
Supplements: Magnesium: 310-420mg; fish oil:1-3g; CoQ10: 30-300mg
Brain Function
Cognitive function declines with age, and may be accelerated by chronic diseases such as hypertension, diabetes. Risk factors include smoking, steroid hormones, lack of mental stimulation, and physical inactivity. Spatial, reference, and visual memory decline.
Hormone treatment: DHEA reduces inflammation in the brain, and may protect against neurological diseases like Alzheimer’s and Parkinson’s.
Food: Wild salmon, avocado, blueberries
Supplements: Acetyl L-carnitine (ALC): 250-500mg; vitamin E:400-1,200IU; fish oil: 1-3g
Muscular System
Age-related loss of skeletal muscle (sarcopenia) results in a decline in muscle strength, which is a major cause of disability from falls and hip fractures, and may contribute to decreased bone density, insulin sensitivity, and aerobic capacity. With age, we are less able to build new muscle tissue.
Hormone treatment: HGH improves muscle mass and strength, and endurance.
Food: Greek yogurt, chickpeas, wild salmon
Supplements: Whey protein; Branched-chain amino acids (BCAA)