Life Extension Magazine March 2010
Don’t Fall Victim to Frailty
By William Davis, MD
Frailty is an age-related deterioration in physical strength and overall performance. We see it in the hunched-over elderly man or woman weakened by fatigue, brittle bones, muscle wasting, and limited mobility.
Frailty is a preeminently preventable condition.
In recent years, the pace of clinical research on how to enhance physical strength and performance in the face of aging has accelerated.
We now have at our disposal a specific set of evidence-based strategies aimed at the underlying biological mechanisms by which we grow weaker over time.
Armed with these techniques, you can regain waning vitality, command better memory, and tightly focus your mental power.
In this examination, we explore a multi-targeted approach to enhance physical stamina, energy, endurance, and overall performance.
Avoiding and even reversing the onset of age-related declines in strength and performance may be achieved simply, effectively, and naturally. The key lies in five core strategies:
One of your primary goals is to have high energy from the moment you wake up and to sustain it throughout the day, followed by a healthy transition to sleep. Although there is more to supercharged physical performance than high energy, having plenty of physical and emotional stamina is a basic requirement.
Here, we will focus on the key nutritional interventions that may help boost your physical strength and performance.
You wouldn’t drive a car without changing the oil every few thousand miles. For the same reason, two essential nutrients should be incorporated into your daily dietary regimen before you take any other steps.
If there is any single nutrient that holds the potential for enormous health and performance gains, it’s vitamin D.
Virtually ignored for decades, vitamin D supple-mentation may help reduce cancer risk, lessen diabetes risk, and enhance bone health, among other remarkable effects.1,2 Vitamin D also enhances physical strength.
1-3A clinical study examining the effect of a miniscule dose of vitamin D (400 IU) along with 800 mg calcium showed improved walking speed and balance by 10-20% in elderly adults.4
As the founder of the Vitamin D Council (www.vitamindcouncil.org), Dr. John Cannell has been among the most vocal advocates of higher intake of vitamin D.
Dr. Cannell reviewed scientific literature concealed for years behind the Iron Curtain during the Cold War years of the former Soviet Union and East Germany. The Russians and Germans had observed marked seasonal variation in athletic performance among athletes: running was faster, jumping higher, weights lifted greater during the summer, and reduced during the winter. Further study led to the practice of vitamin D supplementation among East German and Soviet athletes, sufficient to restore blood levels to that of summer sun exposure with resultant year-round consistent physical performance.5
I have confirmed these published findings in over 1,000 patients with greater effects using higher dose vitamin D supplements. In our clinic, achieving target 25-hydroxyvitamin D blood levels of 60-70 ng/mL has yielded greatly augmented benefits, compared to those obtained at lower levels. In our experience, most men and women require average doses of 5,000-6,000 IUs per day to achieve this blood level of vitamin D. Individual needs can vary, being substantially higher or lower. Testing blood levels is therefore an absolute necessity if precise dosing is desired.
Iodine deficiency sets a cascade of energy-depleting effects in motion.
When iodine is deficient, thyroid function diminishes, and thyroid hormone levels drop, which may lead to a hypothyroid state.6 Standard blood thyroid testing can suggest hypothyroidism if there is an increase in Thyroid Stimulating Hormone (TSH) and low free Thyroxine (T4).6 Symptoms of hypothyroidism include decreased energy, sleepiness, low moods, and poor capacity for exercise.7 One of the earliest and most visible signs of iodine deficiency is thyroid gland enlargement (goiter). Iodine deficiency limits physical performance from mild to profound degrees, depending on severity.
While iodine deficiency had been a thing of the past since the introduction of iodized salt in the early 20th century, it has returned. Iodine intake has been steadily decreasing in the US.8 Ironically, insufficient iodine intake primarily affects the most health-conscious: people who avoid iodized salt, processed foods, and meat. People who exercise vigorously can be among the most iodine-deficient, since substantial quantities of iodine are lost in sweat.9
Iodine replacement is easy. There are a number of iodine supplements that provide various forms of iodine. Choices include molecular iodine (often as drops) and kelp tablets (dried seaweed). While the Recommended Daily Allowance (RDA) for iodine is 150 mcg for non-pregnant adults, some data suggest that human need for ideal health may be greater, perhaps even approaching the experience of the Japanese, who ingest milligram doses (more than 1,000 micrograms).10 In my clinic, we prescribe 500-1000 mcg (0.5-1.0 mg) of iodine per day from kelp tablets with success.
For those desiring higher levels of iodine to restore depleted iodine levels, a specialized form of iodine may be helpful, providing 12.5 mg iodine (12,500 micrograms as molecular iodine and potassium iodide) per tablet. Anyone with suspected thyroid disease should consult their health provider before initiating iodine supplementation.
DHEA and Pregnenolone: The Ultimate “Bioidentical” Hormones
Restoring hormones to more youthful levels is a key strategy for maintaining strength as you age. With the passage of time there is an inevitable decline in hormones that sustain energy and performance.11,12 As these hormones recede, energy and performance diminish along with them.
There has been a lot of fuss over whether or not “bioidentical” hormones—estrogens, progesterone, and testosterone that are identical to those naturally found in the human body—are superior to non-bioidentical forms dispensed by the drug industry. The FDA is currently considering clamping down on the availability of bioidentical hormones and the claims that they are safer and superior to non-bioidentical hormones, despite a groundswell of grassroots support for them. The argument has pitted anti-aging practitioners and the public, as well as the likes of Oprah and Suzanne Somers, against Big Pharma and the FDA—the two forces trying to squash the bioidentical hormone movement.
Regardless of heavy-handed FDA policies, we already have access to hormones identical to the original human form that require no prescription and yield hormones the human body recognizes as bioidentical: DHEA and pregnenolone. These two hormones are precursors to the other hormones at the center of the bioidentical hormone controversy, such as estrogen and testosterone. We therefore already have, in effect, two very effective over-the-counter, non-prescription forms of bioidentical hormones.
Dehydroepiandrosterone (DHEA) is a hormone secreted by the adrenal glands in large quantities during our 20s and 30s. DHEA levels begin a sharp decline at age 30 in men and age 40 in women, along with declining muscle mass, bone density, sex hormones, growth hormone, and increasing body fat. The decline accelerates after age 50. By age 70, DHEA blood levels are usually 20-30% or less of youthful levels.11
13In women with androgen deficiency, DHEA supplementation has been reported to increase alertness, stamina, and sexual interest.14 DHEA supplementation increases testosterone modestly in women and slightly increases andro-stenedione levels in men, while increasing physical and psychological well-being in both genders.15 Most studies documenting the physical and emotional benefits of DHEA have examined doses between 10 and 100 mg per day, the quantity required in most people to restore blood levels to match that of the third decade of life.11 Physical performance enhancement is best obtained with doses of no more than 100 mg per day, usually 10-25 mg per day in women and 25-50 mg per day in men. Anecdotally, benefits are amplified if DHEA is used in combination with testosterone in men, and combined with progesterone in women.
Though difficult to quantify, DHEA replacement helps many people feel better: more physical stamina, a brighter outlook, and more “get up and go.” Problems seem less overwhelming and “lows” tend not to be quite as low.11,15 Though there are clinical data to support these “soft” effects, they are inconsistent.
In the author’s experience, people who start out with sluggishness, low energy, and a negative outlook, accompanied by a low DHEA level (measured as a DHEA-S level of <250 µg/dL), are the most likely to experience positive results with DHEA replacement.
Side effects at high doses (50-200 mg per day) may include acne, increased facial hair, and increased perspiration. Individuals with hypertension or who are taking the drug diltiazem should not supplement with DHEA except under the close supervision of a doctor. Those with breast or prostate cancer or a family history of these conditions should not take DHEA supplements unless specifically directed to do so by their doctor.
Pregnenolone is an adrenal gland hormone, the first hormonal product synthesized from cholesterol, and the basic precursor from which all sex hormones (testosterone, progesterone, and estrogens) and adrenal hormones (DHEA, cortisol, and aldosterone) are made.16 Like DHEA, pregnenolone levels peak during our 20s and 30s, followed by a decline with aging and the passing of the years, particularly in women.17
Pregnenolone and DHEA may have special relevance in the 21st century. The low-fat dietary mistake of the last 30 years has led to excessive carbo-hydrate intake. Pregnenolone and DHEA levels may drop dramatically in those with high carbohydrate intakes or higher levels of fasting blood sugar. In clinical studies, infusions of glucose (blood sugar) in healthy adults reduced pregnenolone levels by 51% and DHEA levels by 57% within 80 minutes.18
Pregnenolone exerts complex effects in the human brain, and is thought to modulate stress and mood. However, among pregnenolone’s effects is enhanced acetylcholine activity, a process that underlies memory and thinking.19 Multiple experimental models suggest that pregnenolone acts as a “neurosteroid” in the brain, a potent modulator of brain excitability.19
Pregnenolone may be especially helpful for females who require increased levels of progesterone and testosterone, since this single agent can increase both. One potential uncommon downside: increased blood pressure. Pregnenolone is the source of multiple hormones, including a class of hormones called mineralocorticoids.20 In susceptible people, this could potentially cause water retention and increased blood pressure.
Supplementation of both DHEA and pregnenolone is generally not advised under the age of 40, unless a health provider has documented low levels. Pregnenolone has antagonistic effects on gamma-amino butyric acid (GABA) receptors in the central nervous system; therefore supplementation with pregnenolone is not recommended for people with a history of seizures.21