You don’t need to be told about the dangers of smoking, especially these days, when cancer victims regularly sue large tobacco companies. Smoking will kill you eventually, either through cancer’primarily lung cancer’or heart disease. Cigarette smoke contains thousands of known carcinogens, and the carbon monoxide inhaled with each puff makes your heart work harder by tying up oxygen circulating in the blood. No sensible person would consider engaging in that undeniably harmful habit.
It’s also true, however, that smoking does offer some benefits, although they’re easily outweighed by the negative health aspects. Smokers who quit often notice weight and bodyfat increases. That relates to how smoking increases resting metabolism by promoting the release of various stress hormones, such as epinephrine and norepinephrine. Those hormones, in turn, have thermogenic effects, thus helping the body metabolize fat. Still, it would be far more sensible to use a thermogenic supplement that features ingredients such as ephedrine and caffeine than to rely on smoking as a fat-loss tool.
Smoking also increases the activity of neurotransmitters in the brain, which affects things like alertness and memory. In fact, nicotine, one of the primary active ingredients in cigarettes, is so effective at promoting the activity of acetylcholine that scientists are trying to figure out a way to harness its positive brain effects to treat such degenerative diseases as Alzheimer’s and Parkinson’s.
From a bodybuilding and athletic perspective, smoking offers few, if any, advantages. Macho baseball players who indulge in chewing tobacco can wind up with not only stained teeth but also cancer of the mouth. The carbon monoxide in tobacco products has a 200-times-greater affinity for oxygen than the hemoglobin circulating in the blood. That plays havoc with both aerobic capacity and energy production.
Smoking has more subtle effects on hormones. It is known to increase cortisol levels, which would produce catabolic effects in muscle, and promote fat deposition in the trunk portion of the body. The medical literature concerning the effect of smoking on sex hormones, such as testosterone and estrogen, indicates mixed results. Some studies show elevated testosterone levels, while others show either no effect or lowered testosterone levels in chronic smokers.
Many studies only measure total testosterone levels. That’s problematic because total testosterone levels don’t necessarily reflect the degree of testosterone activity in the body; about 98 percent of circulating testosterone is bound to plasma proteins synthesized in the liver, such as sex-hormone-binding globulin (SHBG) and albumin. Only the 1 and 2 percent of unbound, or free, testosterone is considered biologically active and capable of interacting with cellular androgen receptors.
Low levels of testosterone in men appear to promote cardiovascular disease. Since cigarette smoking is also associated with cardiovascular disease, a recent study examined the effects of smoking on free-testosterone levels in 25 smokers, all of whom smoked at least 25 cigarettes daily, and 25 healthy men who had never smoked.1 The subjects ranged in age from 17 to 60. Medical residents were excluded from the study because past studies show that they have lower-than-normal testosterone levels, most likely due to high stress.
The results showed that the smokers had significantly higher levels of both total and free testosterone than the nonsmokers, but they also had higher levels of SHBG, which effectively tied up much of their active, free testosterone. That made the differences in testosterone levels insignificant. There were no differences in estrogen levels between the groups. The increased SHBG levels in the smokers was thought to result from an increase of conitine, the primary metabolic waste product of nicotine.
Potential smokers or those already addicted should also be aware that smoking is associated with higher resting insulin levels and insulin resistance,2 effects that would likely cancel out any beneficial effects of smoking on metabolism and fat loss.
SHBG and Diet
As noted above, smoking cigarettes increases free testosterone levels, but any beneficial aspect is negated by the concomitant increase in sex-hormone-binding globulin, a protein that ties up testosterone in the blood. Smoking isn’t the only influence on SHBG, however, and knowing how other factors affect that blood protein can help you control your own testosterone levels.
Diet affects SHBG levels and, consequently, free testosterone activity. A study published last year examined the relationship between diet and SHBG levels in 1,552 men between the ages of 40 and 72.3 Its main finding was that dietary protein has an inverse relationship with SHBG; that is, as protein intake drops, SHBG levels increase, thus reducing the activity of testosterone in the body.
In older men the decreased availability of free testosterone is linked to cardiovascular disease and adverse effects on sexual drive and function and bone density. Other studies show that low testosterone levels may promote the onset of Alzheimer’s disease by increasing the level of a brain protein associated with that disease, beta-amyloid.
In attempting to determine what it is about dietary protein that lowers SHBG in men, the authors at first pointed to increased insulin levels induced by a high-protein diet. Insulin is known to lower SHBG and thus increase free testosterone levels in the blood. This is, in fact, one reason why many athletes today combine insulin injections with various anabolic steroid drugs and growth hormone: Together they provide a synergistic anabolic effect far greater than any one of them alone.
Dietary protein can promote insulin release because of the presence of specific glucogenic amino acids that stimulate the release of insulin. That’s also a frequent critique of the popular low-carbohydrate diets, which seek to promote bodyfat losses by controlling insulin through a limited carbohydrate intake. The critics point out that if the main purpose of such diets is to control insulin release, the goal is limited by the usual high-protein content of low-carb diets.
If the effect of dietary protein in promoting higher free testosterone levels emanates from an insulin-stimulating effect, wouldn’t carbohydrates, which promote the greatest insulin secretion, work even better? Surprisingly, carbs appear to have no relationship to SHBG levels, according to the researchers, which led them to believe that the effect of protein on SHBG must come from somewhere other than insulin.
The study found that a higher fiber intake is also linked to higher levels of SHBG and, thus, lower levels of free testosterone. That’s one mechanism suggested for the frequent finding that dietary fiber appears to protect against testosterone-related cancer, such as prostate cancer.
In addition to protein and fiber, dietary fat also influences the levels of SHBG and free testosterone. A higher-fat intake lowers SHBG and increases free testosterone levels, while lowfat diets have an opposite effect. Studies done with bodybuilders clearly show that consuming less than 20 percent of daily calories as fat leads to a drop in testosterone.
That finding also has health implications. Many researchers believe that a high dietary fat intake promotes various types of diseases, including cardiovascular disease and, in men, prostate cancer. They suggest that a diet emphasizing higher carb and fiber intake, with a fat content of as low as 10 percent of calories, would offer protective effects against prostate cancer. As noted earlier, though, a high-fiber, lowfat diet tends to lower testosterone levels, and, ironically, that’s the mechanism for the protective effects of such diets.
The point is illustrated by another study, in which 27 obese men were put on a three-week diet and exercise program.4 Their diet consisted of a high-carbohydrate (75 to 85 percent), high-fiber (30 to 40 grams), lowfat (less than 10 percent of calories), moderate-protein (15 percent) regimen. The diet and exercise program led to lowered insulin levels’likely due to the higher fiber intake, which modulates carbohydrate absorption’and a higher SHBG level.
The researchers felt that the lowered free testosterone (by way of increased SHBG) and insulin levels would protect against prostate cancer. From a bodybuilding perspective, that diet would have either a neutral or catabolic effect on muscle growth. Thus, bodybuilders interested in health are left with a quandary.
There may be solutions, however. Newer research shows that the relationship between testosterone and prostate cancer isn’t as clear-cut as was previously believed. Another emerging theory suggests that the underlying causes of prostate cancer may come from long-term oxidation processes occurring at a cellular level in prostate tissue. That would explain why other studies show that antioxidant nutrients, such as lycopene, vitamin E and selenium, among others, appear to reduce prostate cancer incidence by 40 percent or more. Recent studies show that omega-3 fats, as found in such fish as sardines, salmon and halibut, also offer protective effects by modifying eicosanoid activity in the prostate gland.
The lesson to be learned here is that if you must engage in practices linked to bodybuilding progress or muscular gains, such as eating a higher-fat diet and even using anabolic steroids, you should consider eating foods high in the protective nutrients mentioned above or take them in supplemental form.
Nandrolone: Body Effects
Nandrolone decanoate is a popular injectable anabolic steroid sold under various trade names, the most familiar being Deca-Durabolin. Deca is an oil-based steroid with a long onset of activity. Its popularity with bodybuilders stems from its alleged pronounced anabolic effects combined with a relatively low side-effect profile. In fact, the worst side effect linked to Deca is that it’s a bad choice if you expect to be tested for anabolic steroid use. That’s because Deca leaves enough trace material in the body to produce positive drug tests even as much as a year after you stop using it.
Because of its long-standing reputation, bodybuilders express little doubt about the anabolic and fat-loss effects of Deca-Durabolin and similar nandrolone drugs, but does that widespread belief coincide with solid scientific confirmation? Studies done with hospitalized or ill patients given nandrolone drugs did show definite anabolic effects, but until recently few studies used hard-training bodybuilders as subjects. A recent study examined the effects on muscle growth and body composition in nine recreational bodybuilders who used 200-milligram injections of Deca-Durabolin for eight weeks.5 Another seven bodybuilders were injected with a placebo. The study featured a double-blind, placebo-controlled protocol, meaning that neither the researchers nor the subjects knew who was taking the real drug.
The authors took measurements of all subjects at the start of the study, after eight weeks and six weeks after all drug use ceased. Neither group showed any differences in side effects, confirming why Deca is so popular with athletes. At the end of eight weeks it did increase total-body mass and bone-free lean mass, but it didn’t have any effect on total bodyfat. Even so, the fat level in the legs of the bodybuilders who used the actual drug did decrease and remained lower after they got off the drug.
The results also revealed that the mass gained in the trunk muscles increased more than the muscle mass gained in the legs. Arm-muscle girth showed no change at all. The only muscle circumference to increase significantly after eight weeks of Deca use was the neck.
The authors didn’t explain why these changes occurred in the bodybuilders using Deca, but they did note that most bodybuilders who use anabolic steroids use several types’both oral and injectable’a process known as stacking. Other popular anabolic drugs often used in conjunction with steroids are growth hormone and insulin. Those more extensive drug combinations likely have a far greater impact on body composition than a single drug, such as Deca-Durabolin.
1 English, K.M., et al. (2001). Effect of cigarette smoking on levels of bioavailable testosterone in healthy men. Clinical Science. 100:661-665. 2 Ronnemma, T., et al. (1996). Smoking is independently associated with high plasma insulin levels in nondiabetic men. Diabetes Care. 19:1229-32.
3 Longcope, C., et al. (2000). Diet and sex-hormone-binding globulin. J Clin Endocrinol Metab. 85:293-296.
4 Tymchuk, C.N., et al. (1998). Effects of diet and exercise on insulin, sex-hormone-binding globulin and prostate-specific antigen. Nutrition and Cancer. 31:127-31.
5 Hartgens, F., et al. (2001). Body composition and anthropometry in bodybuilders: regional changes due to nandrolone decanoate administration. Int J Sports Med. 22:235-41.