There may be more myths and misunderstandings about obesity than
about any other major health epidemic. Americans are constantly
besieged with faulty or incomplete weight-loss information—some of it
from mainstream sources. To lose weight, we are advised to avoid entire
food categories (such as carbohydrates or fats) or to eat only one food
category (proteins, for instance). And every new fad diet is
accompanied by an avalanche of new products and marketing hype as
companies try to cash in on Americans' desperate desire to slim down.
The result is a stream of conflicting information that leaves many
people confused.
Worse yet, none of it seems to be working. The National Institutes
of Health (NIH) estimate that more than half the adult population of
the United States is overweight (defined as a body mass index [BMI] of
25 to 30). A significant number of these people are obese (defined as a
BMI greater than 30). The obesity epidemic is even beginning to affect
children, whose obesity rates have doubled in the past two decades (NIH
2005). And instead of declining, obesity rates are rising, along with
the frequency of conditions that are closely associated with obesity,
such as type 2 diabetes and metabolic syndrome.
The government's answer to the growing epidemic of obesity has been
to recommend more exercise and a balanced diet. While there is no doubt
these strategies are important, they also display an incomplete
understanding of the biological and hormonal changes that underlie
obesity among aging adults. The fact is that as we age, we undergo
physiological changes that encourage weight gain. These include
hormonal changes and alterations in the way our bodies process
nutrients.
Vitamin Depot Online.com (LE) believes that, in addition to a sensible,
balanced diet and exercise, the only way to successfully lose weight is
to address the underlying hormonal imbalances that promote weight gain.
Ideally, by using bioidentical hormone replacement, dieters can restore
their hormonal profile to what it was at the age of 25, an age at which
weight gain is less often a problem. In addition, numerous dietary
nutrients have been shown to encourage weight loss. In this chapter, LE
presents a specific plan, based on scientific literature that will help
aging people lose weight.
Why Middle-Aged Men Gain Weight
About age 30 to 35, most men (and some women) notice they are
gaining weight around the middle. Their pants become tight and at some
point no longer fit. The words “pot belly,” “beer belly,” or “spare
tire” are sometimes used to describe the medical condition called
“abdominal obesity.” This sort of fat accumulation greatly increases
the risk of cardiovascular and other diseases.
Low testosterone = abdominal fat gain
As it turns out, there is a scientific explanation for the tendency
toward abdominal obesity among middle-aged men. As men age, their
levels of free testosterone decline, and levels of estrogen and insulin
increase. This is partly because aging men convert much of their
testosterone into estradiol, a form of estrogen. Of the remaining
testosterone, much is bound to sex hormone–binding globulin, a protein
in the blood, and is not biologically active. Studies have shown that
men with low free testosterone have higher rates of coronary artery
disease, mental depression, and dementia (Tan et al 2004).
The idea behind testosterone replacement therapy is to restore the
level of free testosterone to that of a healthy 25-year-old to
counteract the effects of increased estrogen. Studies have shown that
fat cells, particularly abdominal fat cells, convert testosterone to
estradiol (Schneider et al 1979; Kley et al 1980; Killinger et al 1987;
Khaw et al 1992). The more belly fat a man accumulates, the greater the
conversion of his testosterone into estradiol. As long as free
testosterone is low and the ratio of estrogen to insulin is high, most
aging men will store fat around their belly (Abate 2002).
Clinical studies have shown that testosterone replacement therapy can provide a variety of benefits.
- In one study of 86 men aged 50 to 70, waist-to-hip ratio and blood
pressure markedly decreased after 60 days of testosterone therapy (Li
et al 2002).
- Another testosterone-replacement study in middle-aged obese
men showed improved waist-to-hip ratio along with a decrease in plasma
insulin and an increase in glucose disposal, suggesting improved
insulin sensitivity (Marin et al 1992).
- In another trial, abdominally obese middle-aged men showed
improved glucose control, decreased abdominal body fat, and improved
sexual function after testosterone therapy (Boyanov et al 2003).
Given that these studies looked only at testosterone levels, one can
only speculate about what the results might have looked like if excess
estrogen and insulin had also been suppressed.
Hormone Therapy for Women
In women, the relationship between excess body fat, testosterone, estrogens, and progesterone is somewhat more complicated.
It is believed that estrogen reduces lipid oxidation at puberty and
in early pregnancy to facilitate efficient fat storage in preparation
for fertility, birth and lactation (O'Sullivan et al 2001; Rosenbaum et
al 1999). This modification in lipid oxidation enables fat storage
without significant changes in dietary fat and caloric intake
(O'Sullivan et al 2001).
The drop in gonadal estrogen production at menopause is associated
with an increase in the waist to hip ratio and an increase in size of
visceral adipose tissue, and administration of estrogen to
postmenopausal women is associated with a lowering of the waist to hip
ratio (Rosenbaum et al 1999). However, as women age, levels of
progesterone and all estrogens (including estriol, estradiol, and
estrone) decline..Progesterone declines much more rapidly than do the
estrogens, leading to “estrogen dominance” (Lee et al 1999) . LE
believes the imbalance of estrogens and progesterone may play a pivotal
role in the dynamics of metabolic obesity and visceral fat accumulation
in aging women.
DHEA and Weight Loss
Testosterone and estrogen are not the only hormones implicated in
weight gain. Low levels of DHEA (dehydroepiandrosterone), a steroid
hormone, have also been linked to increased weight gain. Virtually
everyone over age 35 experiences a significant reduction in DHEA.
Studies suggest that supplementing with DHEA produces beneficial body
composition changes (Villareal et al 2000; Villareal et al 2004).
For example, a 6-month trial in aging men and women with low DHEA
levels demonstrated that 50 mg of DHEA per day reversed age-related
changes in fat mass (Villareal et al 2000).
Another study showed that DHEA decreased abdominal obesity and
improved insulin action. This randomized, double-blind,
placebo-controlled trial evaluated 50 mg of DHEA per day for 6 months
in 56 individuals with age-related decline in DHEA levels. The study
showed that DHEA was associated with significant decreases in visceral
and subcutaneous fat and improved insulin sensitivity (Villareal et al
2004).
Note: In woman DHEA can convert to testosterone, which is acceptable as long as testosterone is kept within proper range.
7-keto DHEA. A metabolite of DHEA called 7-keto
DHEA has also attracted considerable attention for its value as a
fat-loss supplement. Like DHEA, 7-keto DHEA levels dramatically decline
with age (Marenich 1979).
In animal studies, 7-keto DHEA boosted fat-burning enzymes (Bobyleva
et al 1993; Bobyleva et al 1997). Studies using 7-keto DHEA supplements
produced encouraging results. For example, researchers assessed the
effects of taking 100 mg of 7-keto DHEA or placebo twice daily for 60
days. Compared with placebo, the 7-keto group lost more body weight
(6.3 lb vs. 2.1 lb). This study also found that supplementing with
7-keto DHEA was associated with a significantly greater percentage of
body fat loss compared with the placebo group (Kalman et al 2000).
Because of the fat burning, or thermogenic effects of 7-keto DHEA,
simultaneous supplementation with antioxidants is recommended to help
guard against excessive free radical production. Animal studies have
shown that 7-keto DHEA is not converted into testosterone or estradiol
(Lardy et al 1995). Unlike caffeine or ephedra, 7-keto DHEA does not
have a noradrenaline-induced central nervous system stimulating effect,
nor does 7-keto increase heart rate or blood pressure.
The Thyroid Connection
There has been a great deal of misunderstanding about the connection
between thyroid hormone and weight loss. Produced in the thyroid gland,
thyroid hormone is the master metabolic control mechanism. A lack of
thyroid hormone (a condition called hypothyroidism) is connected to
weight gain, as well as dry hair and skin, fatigue, and sluggishness.
Overweight people may want to check their thyroid levels to make sure
they aren't lacking thyroid hormone. If they are, a physician may
prescribe thyroid hormones to correct the condition.
In the 1960s and 1970s, the connection between hypothyroidism and
weight gain caused some people to assume they could speed up their
metabolism and lose weight by using supplemental thyroid hormones. This
led to an abuse of thyroid hormone as people created an artificial
state of excess thyroid hormone (a condition medically known as
hyperthyroidism). Hyperthyroidism can cause weight loss as well as
irregular heartbeats, sweating, and tremors. Although people taking
supplemental thyroid hormones may have lost weight, they were losing
lean muscle mass in addition to undesirable body fat (Braunwald et al
2001).
Today our understanding of the relationship between thyroid hormone
and weight loss is more complete. It works like this: when calorie
intake is drastically reduced, the activity of an enzyme called
5'-monodeiodinase is reduced; 5'-monodeiodinase is necessary to convert
the thyroid hormone T4 into T3. As a result, the levels of T3 drop
(Merimee et al 1976; Carlson et al 1977; Beer et al 1989; Wadden et al
1990). T3 is the stronger form of thyroid hormone. The connection is
especially valid when it comes to a reduction in carbohydrate calories:
- As little as 50 g of glucose reverses the change in T3 (Burman et al 1979)
- Replacement of carbohydrate with fat results in thyroid
hormone changes typically observed during times of starvation (Danforth
et al 1975; Azizi 1978)
- P rotein consumption improves the rate of T3 generation more than carbohydrate consumption (Harris et al 1978)
Therefore, consuming more carbohydrate calories during dieting can
counteract the drop in T3 associated with dieting. Alternatively,
decreased T3 levels can be directly replaced. Some older clinical
studies testing this theory were promising. However, later studies
showed that direct T3 supplementation by dieters was connected with
muscle wasting (Gardner et al 1979; Vignati et al 1978). During
fasting, administration of large doses of T3 caused even more severe
muscle wasting (Carter et al 1975).
More recent studies suggest that using very low doses of replacement
thyroid hormone during dieting, once the body has switched over from
carbohydrate burning to fat burning, may not be associated with muscle
breakdown (Nair et al 1989; Byerley et al 1996, Pasquali et al 1984).
The Insulin Trap
Recent advances in dietary science have highlighted the crucial role
of insulin in weight gain. Produced in the pancreas, insulin is a
critical hormone for the control of blood sugar (glucose). Its job is
to transport glucose into cells, where the glucose is burned as fuel.
While this process is necessary for life, abnormalities in the
insulin-glucose system caused by aging, lack of exercise and poor diet
can cause major health problems. In aging, cells become more resistant
to the effects of insulin. As cells become increasingly insulin
resistant, the body compensates by increasing the number of insulin
receptors on cells and secreting more insulin in an attempt to drive
more blood sugar into muscle and liver cells (Fulop 2003).
Insulin resistance is a dangerous condition. Research suggests that
adipose tissue (fat) is a source of pro-inflammatory chemicals that
have a role in the development of insulin resistance (Sharma AM et al
2005). Insulin resistance is associated with obesity (in particular,
abdominal obesity) (Greenfield JR et al. 2004). It is also associated
with aging muscle (Nair KS 2005), physical inactivity, and genetics.
This increase in insulin (called hyperinsulinemia) and decreased
insulin sensitivity have a number of harmful effects, including
contributing to diseases associated with being overweight (Zeman et al
2005; Garveyet al 1998).
Over time, high insulin and insulin resistance may lead to type 2
diabetes in susceptible individuals, a major risk factor for heart
disease. A study sponsored by the NIH showed that over a 10-year
period, hyperinsulinemia was associated with increased all-cause and
cardiovascular mortality, independent of other risk factors (NIH 1985).
Controlling insulin levels as we age is essential for overall
health, longevity, and weight management. An increasing number of
physicians recognize the role of insulin resistance in the current
obesity epidemic. The good news is that nonprescription drugs and
low-cost dietary supplements that have demonstrated beneficial effects
upon insulin action are already available.
Fiber Reduces Insulin Spike
When it comes to weight loss, fiber has not received the attention
it deserves. The recent focus on carbohydrates has led some people to
reduce their intake of whole fruits and some vegetables because these
foods contain carbohydrates. By doing this, those dieters deprive
themselves of the many benefits of a naturally fiber-rich food source.
According to the American Heart Association (AHA) and the National
Cancer Institute (NCI), Americans should consume about 30 g or more of
fiber every day. The actual average consumption, however, is between 12
and 17 g (AHA 2005; NCI 2005).
Consumed before a meal, soluble fiber has multiple benefits. First,
it is filling and causes people to eat less because they are satiated
sooner. Anecdotally, LE has received reports that some people can
actually cut the size of their meals in half by consuming a glass of
soluble fiber mix before eating.
Equally important, consuming fiber before meals can reduce the rapid
absorption of simple carbohydrates (such as refined sugar) and modulate
blood sugar levels (Anderson et al 1993). A review of clinical studies
of fiber shows that it has numerous weight-loss benefits, including the
following:
- Soluble fiber-rich bread improved glycemic control, reduced blood
pressure, and decreased cholesterol and triglyceride levels (Nizami et
al 2004).
- Consumption of an additional 14 g of fiber per day for more
than two days was associated with a 10 percent decrease in calorie
intake and body weight loss of 1.9 kgover 3.8 months (Howarth et al
2001).
- A prospective cohort study showed that weight gain is slowed
with higher intake of high-fiber, whole-grain foods, whereas study
subjects put on more weight when consuming refined-grain foods (Liu et
al 2003).
- A prospective, randomized, double-blind study showed that
soluble fiber supplements can increase post-meal satisfaction (satiety)
significantly (Heini et al 1998).
- A randomized controlled clinical trial demonstrated that
soluble fiber can lower lipids and plasma glucose levels (Aller et al
2004).
- A clinical trial suggested that a diet rich in fiber may lower blood pressure moderately (He et al 2004).
- A highly regarded study in the New England Journal of Medicine
showed that a high-fiber diet (50 g fiber, including 25 g soluble and
25 g insoluble) lowered 24-hour plasma glucose and insulin
concentrations (Chandalia et al 2000).
Soluble fiber is found in oat bran, barley, vegetables, fruits, and
other foods. However, for weight-management purposes, it is important
to have soluble fiber before every meal. Therefore, soluble fiber
supplements (such as powders or capsules) should be kept where meals
are consumed, such as the kitchen or the office.
Some people shy away from fiber because they experience lower bowel
disturbances if too much fiber is consumed at first. This can be
avoided by beginning with a low dose of fiber before each meal and
gradually increasing doses over a two- to three-week period. Once the
body adjusts to increased fiber intake, gastrointestinal side effects
usually disappear.
How to Use Fiber Supplements
Before every meal, consume enough soluble fiber to slow the rapid
carbohydrate absorption that can cause insulin levels to spike.
Consuming soluble fiber before each meal also enables you to feel
satisfied sooner, thereby reducing the number of calories consumed.
The type of dietary fiber to use is an important consideration. To
help induce weight loss, purified soluble dietary fibers, such as
pectin, guar, psyllium, glucomannan, alginate, and beta-glucan, help
normalize blood glucose and have an antidiabetic effect (Trepel 2004).
A study showed that 7 g of soluble fiber (psyllium) significantly
decreased hunger feelings, decreased food intake, and blunted increases
in serum glucose-insulin levels (Rigaud et al 1998). A trial in
patients with type 1 diabetes illustrated that 16 g of soluble fiber
(guar) daily significantly decreased blood glucose after eating
(Lafrance et al 1998). Another study showed that as few as 5 g of
soluble fiber (alginate) significantly decreased the post-meal rise in
glucose and insulin (Torsdottir et al 1991).
Some people find it difficult to consume high-dose fiber powder
drinks before every meal. Yet taking only a few grams of specialized
soluble fiber blends can produce remarkable benefits. Led by University
of Toronto scientist Vladimir Vuksan, Ph.D., researchers combined
glucomannan with two other soluble fibers (xanthan and alginate) in an
exact ratio and added mulberry concentrate (20:1) to enhance
glycemic-control and lipid-lowering effects (Andallu et al 2001). This
proprietary blend is called PGX.
At the 2004 meeting of the American Diabetes Association (Orlando,
Florida), results of two studies using PGX fiber blend were presented
by researchers from the Risk Factor Modification Centre at St.
Michael's Hospital and the University of Toronto (Vuksan et al 2004):
- Study participants who took 3 g of the fiber blend had a 65 percent
reduction in post-meal glucose elevation after consuming a 50-gram
acute glucose challenge.
- Study participants who took 3 g of the fiber blend (three
times a day, before meals) had a 23 percent reduction in post-meal
glucose, a 40 percent reduction in post-meal insulin release, and a
55.9 percent improvement in whole-body insulin sensitivity scores.
- Study participants taking the fiber blend reduced body fat
by 2.8 percent from baseline by the end of the three-week study period.
Optimal weight-loss benefits occurred when six PGX capsules were
taken before meals, although some studies indicate as few as two
capsules might produce some results (Vuksan et al 2004).
An advantage of PGX is that its benefits may be obtained by
swallowing capsules, which usually do not cause intestinal distress.
However, to induce early satiety, drinking a soluble powder mix before
meals is preferable to swallowing capsules.
The typical dose for soluble fiber drink mix is 8 to12 g taken
before meals. Begin with only 4 g before each meal for the first week
or two to allow your digestive system to adjust to higher fiber intake.