Thursday, March 28, 2013

Diet Wars : Who wins in the battle of the bulge reduction? by Jerry Brainum

   In an effort to clear up the considerable confusion about which diet is most effective for fat loss, researchers from Stanford University spent a year testing four popular diet plans on 311 overweight women, aged 25 to 50. Published in the prestigious Journal of the American Medical Association, the study examined the Atkins low-carb plan, which starts at 20 grams a day of carbs and gradually increases to 50 grams a day; the Zone diet, which features a percentage formula of 40-30-30 for carbs, protein and fat; the LEARN plan, a traditional balanced diet usually suggested for promoting good heath, consisting of 55 to 60 percent carbs and less than 10 percent saturated fat intake; and the Ornish diet, which contains 10 percent fat or less. The Zone and LEARN plans call for a specific daily calorie limit, while the Atkins and Ornish plans don’t.

   The greatest criticism of low-carb diets is that their high fat content predisposes dieters to cardiovascular disease. That was adamantly denied by Robert Atkins, M.D., the heart specialist who developed the Atkins diet. Atkins suggested that control of insulin, a cornerstone of low-carb diets, would more than make up for eating lots of fat. Besides, because carbs are so restricted on the Atkins plan, most of the dietary fat is oxidized.

   Dean Ornish, also a cardiologist and whose diet philosophy is the opposite of Atkins when it comes to eating fat, noted that levels of low-density lipoprotein, or LDL, which is linked to cardiovascular disease, rose in those who followed a low-carb diet during the study. As one of the authors noted, however, blood triglycerides dropped more than 30 percent in the low-carb dieters. That’s significant because when triglycerides drop, you get a larger, more buoyant LDL molecule. The type of LDL linked to cardiovascular disease is small and dense and is more likely to oxidize than the larger version. LDL is dangerous only when oxidized.

   Other critics of the new study said that while those on the Atkins diet clearly lost more fat initially, after a year the differences in fat loss from the diets become similar. The women on the Atkins plan found it easy to follow, with no precise guidelines other than carb restriction. The high-protein feature of the Atkins diet brings greater satiety, making it far easier to stick with than lowfat, high-carb diets like the Ornish plan, on which most people get ravenously hungry.

   Those in the Atkins group also had elevations in high-density-lipoprotein cholesterol, which protects against cardiovascular disease. HDL tends to rise with a higher fat intake, an effect confirmed with those who followed the Ornish lowfat plan. No change at all occurred in their HDL levels, although LDL did drop.

   Because most people diet to lose bodyfat, it’s just common sense that the diet with the best results would be more motivating. Losing fat is important for health reasons because excess bodyfat triggers inflammation all over the body that’s linked to all forms of disease and mortality, including cardiovascular disease and cancer.

   Bodybuilders used low carb-diets long before they became popular with the public. In fact, most top bodybuilders still rely on carb restriction to get into contest condition. They know that when you control insulin release, you rapidly tap into bodyfat stores. It’s true that glycogen, which is the major exercise fuel source in muscles, is itself a complex carbohydrate, but it’s not that difficult to take your carbs in strategically, meaning before and after training. That makes for maximum fat burning while providing needed energy.

Gardner, C.D., et al. (2007). Comparison of the Atkins, Zone, Ornish and LEARN diets for change in weight and related risk factors among overweight women. JAMA. 297:969-77.

©,2013, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

Want to build muscle and lose fat without using drugs? Check out JERRY BRAINUM'S BOOK AT www.jerrybrainum.com

Sunday, March 10, 2013

High Protein and Fat Oxidation by Jerry Brainum


    Most fat-loss diets recommend a higher protein intake, and for good reason. More protein yields a greater thermogenic effect, meaning calories are converted into heat and not stored as bodyfat. Protein boosts calorie burn-off by 20 to 30 percent, compared to 5 to 10 percent for carbs and 0 to 3 percent for fat. In addition, despite the fact that some of the amino acids in dietary protein can be converted into glucose, protein intake is not associated with the large release of insulin that occurs when you eat high-glycemic, or rapidly absorbed carbohydrate. Because a high insulin count is linked to both retention and synthesis of bodyfat, the control of insulin also aids fat loss.
     Fat oxidation, or burning, is impaired in people who have a lot of bodyfat for a number of reasons. For one thing, they often have a blunted sympathetic hormonal response that affects hormones involved in fat mobilization, such as epinephrine and norepinephrine. Most of the supplements touted to help reduce bodyfat modulate the blunted sympathetic response and may improve the blunted calorie burn.
      A recent study examined the effect on fat oxidation in obese people who ate high-protein meals that included carbohydrates of various glycemic-index contents.1 The diets consisted of the following:
1) Control diet—14 percent protein, glycemic index 65 percent
2)High protein, high GI—33 percent protein, GI 74
3) High protein, low GI—35 percent protein, 45 GI
The glycemic index is a measure of how rapidly the body absorbs glucose. The highest GI is 100, often represented by white bread or glucose itself. It was originally developed for diabetics, since rapid carbohydrate absorption can influence their insulin requirements, but it’s also relevant to nondiabetics. The GI system applies only to single foods and is less applicable to mixed meals. For example, a meal containing carbohydrate and protein tends to result in a lower GI number, since protein and fat considerably blunt carb uptake.
     What the study found was that fat oxidation wasn’t suppressed in obese people who ate meals high in protein. Surprisingly, the GI number of the meal didn’t have any effect on the boost in fat oxidation they got from eating protein. The effect appears specific to those with higher bodyfat, however. When people who have low bodyfat eat a high protein meal, fat use is spared.
    The study underscores the importance of a high protein intake for anyone who wants to lose excess bodyfat. Not only does it aid fat oxidation, but it also spares lean mass at the expense of bodyfat. That, in turn, maintains the resting metabolic rate, which would otherwise drop with a loss of lean mass—something that occurs in those who eat low-calorie diets with insufficient or poor protein, such as plant foods, and who don’t engage in resistance exercise. In those instances, the loss of vital lean mass guarantees a regain of lost bodyfat. That explains the 95 percent recidivism of most diets, particularly the ones that feature both insufficient protein intake and lack of weight-training exercise.
     Another way that a high-protein diet aids fat loss is by inducing increased satiety. Eating a meal high in protein provides the greatest feeling of fullness, followed by carbs, then fat. A recent study compared two different amounts of casein as the sole source of protein in a diet that also contained 55 percent carbs.2
Twelve men and 12 women stayed for 36 hours in a respiration chamber. Their diets contained either 25 percent or 10 percent of energy derived from casein. That was the only difference between the two diets; total calorie intake was identical because the fat content of the diets was manipulated.
    As a slowly absorbed milk protein, casein releases amino acids over a seven-hour period. The 25 percent casein diet resulted in a 2.6 percent higher 24-hour total energy expenditure than the 10 percent casein diet. Those in the higher casein group also showed a higher sleeping metabolic rate and a more positive protein balance than the 10 percent group, and satiety was 33 percent higher. That resulted in a whopping 41 percent less hunger than in the 10 percent group, which explains why it’s far easier to stick with a higher-protein diet than a lower-protein, higher-carb, lowfat diet.
     A previous study, which used the same measures of casein during breakfast, found that the 25 percent casein meal was more satiating than the 10 percent version, an outcome attributed to prolonged elevation of plasma amino acids. The lessened hunger in the later study was also attributed to the prolonged release of amino acids from casein.
   Although both diets contained the same level of carbohydrate (55 percent), the plasma glucose levels were lower in the 25 percent diet, likely related to slower gastric emptying. Those getting the 25 percent casein diet had lower insulin counts, which aids in fat reduction. The 25 percent diet also produced lower amounts of intestinal hormones that modify appetite, again thought to occur because casein delayed gastric emptying.

References
1 Batterham, M., et al. (2008). High protein meals may benefit fat oxidation and energy expenditure in individuals with higher bodyfat. Nut Dietetics. 65:246-52.
2 Hochstenbach-Waelen, A., et al. (2009). Comparison of two diets with either 25 percent or 10 percent of energy as casein on energy expenditure, substrate balance and appetite profile. Am J Clin Nutr.89(3): 831-838.

©,2013, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

 

Have you been ripped off by supplement makers whose products don’t work as advertised? Want to know the truth about them? Check out Jerry Brainum's book Natural Anabolics, available at JerryBrainum.com

 
 

The Applied Ergogenics blog is a collection of articles written and published by Jerry Brainum over the past 20 years. These articles have appeared in Muscle and Fitness, Ironman, and other magazines. Many of the posts on the blog are original articles, having appeared here for the first time. For Jerry’s most recent articles, which are far more in depth than anything that appears on this blog site, please subscribe to his Applied Metabolics Newsletter, at www.appliedmetabolics.com. This newsletter, which is more correctly referred to as a monthly e-book, since its average length is 35 to 40 pages, contains the latest findings about nutrition, exercise science, fat-loss, anti-aging, ergogenic aids, food supplements, and other topics. For 33 cents a day you get the benefit of Jerry’s 53 years of writing and intense study of all matters pertaining to fitness,health, bodybuilding, and disease prevention.

 

See Jerry's book at  http://www.jerrybrainum.com

 

Want more evidence-based information on exercise science, nutrition and food supplements, ergogenic aids, and anti-aging research? Check out Applied Metabolics Newsletter at www.appliedmetabolics.com

 



Friday, March 1, 2013

Carb Blocker, Protein Shocker by Jerry Brainum

                                     Does tea interfere with digestive enzymes?

    Several studies have shown that drinking green tea appears to help you lose bodyfat, perhaps because of its caffeine and its potent antioxidants, which may increase resting metabolism. Some studies show that green tea inhibits the enzyme lipase, which is required to digest fat. Other studies show that both black and green teas inhibit the activity of alpha-amylase, an enzyme involved in carbohydrate, especially starch, digestion.
      While many studies examining the effects of tea on enzyme activity have had an  in vitro or test-tube, design, a newer study looked at the effects of black, green and mulberry teas on human subjects.1 In it subjects took concentrated tea extracts before eating meals containing either carbohydrates or fat.
The tea extracts didn’t affect fat absorption but did induce a 25 percent malabsorption of carbohydrates. The active ingredients in the extracts were the equivalent of drinking five to 20 cups of tea daily. The authors note that if you ate 400 grams of carbs daily, reducing the absorption of 25 percent of those carbs would lead to a loss of 16 kilograms, or 35 pounds, of fat a year with no other changes in diet or exercise. They also warn, however, that inhibiting that much carb absorption could lead to some side effects, such as intestinal gas and diarrhea.
     Another study examined the effects of the active ingredients in tea, the polyphenols, on digestive enzymes that break down carbs (a-amylase), fat (lipase) and protein (pepsin, trypsin).2 The in vitro experiment found that in the presence of 0.05 milligrams per milliliter of tea polyphenols, a-amylase, pepsin, trypsin and lipase activity was inhibited by 61 percent, 32 percent, 38 percent and 54 percent, respectively
The interference with protein-digesting enzymes (pepsin and trypsin) may be a problem for bodybuilders. It isn’t clear from the study how much of the tea polyphenols would produce the effect. Odds are, though, that a high concentration would be required. That’s consistent with previous studies showing high levels of green tea interfered with thyroid function. The amount needed to produce the effect would be hard to reach, and the same may be true for protein enzymes. Those who are concerned may opt to take green tea supplements separately from when they have protein meals and supplements. You wouldn't want to go overboard with green tea supplements anyway, since high doses are linked to liver problems.
    The enzyme inhibition promoted by tea polyphenols was considerably more potent for fat and carbs than protein. For those seeking to lose bodyfat, taking tea supplements with meals high in fat or carbs may prove beneficial. Recent research shows that ingesting green tea supplements with milk proteins, such as whey or casein, causes the active polyphenols in the tea to bind to the proteins, possibly inactivating the polyphenols. For this reason, it's best to ingest any type of tea supplement away from concentrated milk protein supplements.
                                                     References
1 Zhong, L., et al. (2006). An extract of black, green and mulberry teas causes malabsorption of carbohydrate but not of triacylglycerol in healthy volunteers. Am J Clin Nutr. 84:551-555.
2 He, Q., et al. (2006). Effects of tea polyphenols on the activation of a-amylase, pepsin, trypsin, and lipase. Food Chemistry. 101:1178-82.

©,2013 Jerry Brainum. Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

Have you been ripped off by supplement makers whose products don’t work as advertised? Want to know the truth about them? Check out Jerry Brainum's book Natural Anabolics, available at JerryBrainum.com

 
 

The Applied Ergogenics blog is a collection of articles written and published by Jerry Brainum over the past 20 years. These articles have appeared in Muscle and Fitness, Ironman, and other magazines. Many of the posts on the blog are original articles, having appeared here for the first time. For Jerry’s most recent articles, which are far more in depth than anything that appears on this blog site, please subscribe to his Applied Metabolics Newsletter, at www.appliedmetabolics.com. This newsletter, which is more correctly referred to as a monthly e-book, since its average length is 35 to 40 pages, contains the latest findings about nutrition, exercise science, fat-loss, anti-aging, ergogenic aids, food supplements, and other topics. For 33 cents a day you get the benefit of Jerry’s 53 years of writing and intense study of all matters pertaining to fitness,health, bodybuilding, and disease prevention.

 

See Jerry's book at  http://www.jerrybrainum.com

 

Want more evidence-based information on exercise science, nutrition and food supplements, ergogenic aids, and anti-aging research? Check out Applied Metabolics Newsletter at www.appliedmetabolics.com