Life Extension Magazine April 2008
Guard Your Precious Proteins Against Premature Aging
By Steven Joyal, MD
An Anti-Glycation Eating Plan
An innovative, easy-to-follow eating plan that reduces the negative impact of age-accelerating dietary glycotoxins in the body is essential. Overall, foods in the fat and meat (protein) groups contain thirty-fold and twelve-fold higher advanced glycation end product (AGE) content, respectively, than foods in the carbohydrate group. On the other hand, fresh fruits, vegetables, whole grains, raw nuts, and other unprocessed, unrefined foods have low levels of glycotoxins.
A key factor in the formation of food-derived glycotoxins is temperature. Foods high in protein and fat (such as animal products like beef, pork, poultry, fish, seafood, and lamb) as well as foods high in fructose that are cooked, heated, or processed at high temperatures are loaded with glycotoxins. High-temperature cooking methods should be used sparingly—certainly not every day and only a few times a week if possible. Instead, preparing food at temperatures less than 250°F minimizes the formation of dietary glycotoxins. Such methods use liquids and lower cooking temperatures and include poaching, steaming, braising, stewing, and slow cooking (as in a crockpot cooker).
Be on the lookout for foods that are broiled, barbecued, grilled, fried, or oven roasted—these cooking methods use high temperatures and dry cooking conditions, which generate high levels of dietary glycotoxins. Here’s a quick comparison of different cooking methods and the resulting glycotoxin content of some common foods.
Although broiling is believed to be a “healthier” cooking method than frying, it doesn’t make much difference whether you broil or fry a chicken breast; you will end up with about the same amount of glycotoxins: 58 kU/g and 61 kU/g, respectively. The AGE content of beef boiled for one hour is 22 kU/g, while broiling beef for just fifteen minutes results in a value of 60 kU/g, roughly triple the glycotoxin content. This is because the temperature involved in boiling beef is much less than for broiling beef.
Typically, beef is broiled at temperatures that exceed 500˚F. Boiling, on the other hand, is a cooking method that uses water and does not exceed a temperature of 212˚F. When it comes to tofu, the choice between raw (8 kU/g) and broiled (41 kU/g) is quite dramatic—broiling generates about five times the glycotoxin level. In comparison, fresh fruits and vegetables barely make the charts for dietary glycotoxins (apples 0.13 kU/g, bananas 0.01 kU/g, and carrots 0.1 kU/g).
Choose Glycotoxin-Free Foods
Glycotoxins found in foods cooked or otherwise prepared under high heat (such as broiling, grilling, and frying) accumulate in tissues and organs throughout the body. But they also remain there for a very long time. Although the rate of absorption of food-derived glycotoxins is not very high, the body’s ability to remove them (through excretion) is limited. Studies show, for example, that although about 70% of the glycotoxins you eat escape being absorbed by the digestive tract (the body does have ways to resist these invaders), only 33% of the absorbed glycotoxins show up in the urine over a 48-hour period. This means that the glycotoxins are deposited in tissues of the body, where they can wreak havoc. So, to help you get started on your anti-glycation eating program, let’s look at how to choose and prepare glycotoxin-free foods.
When it comes to eating to prevent diabetes, please remember that it’s not only what you eat that’s important, it is how it is prepared. For example, if you have diabetes, given a choice between roasting, grilling, or poaching salmon, which cooking method should you select if you want to help avoid the food-derived glycotoxins that promote nerve and blood vessel damage, both of which cause and contribute to major complications of diabetes? If you guessed poached salmon, you’re right.
Cooking foods using intense heat and without water or other liquids, such as broth or wine, causes the sugars to bind non-enzymatically with proteins (collagen and elastin fibers) to form glycotoxins. Visual evidence of this chemical reaction is the browning reaction seen in food cooked under high, dry heat. The cookies and cake in the oven, the chicken on the grill, and the potatoes in the frying pan are all browning and manufacturing AGEs and ALEs, increasing your risk of developing cardiovascular complications and speeding up the aging process itself.
Whether or not you already have high blood glucose levels, which typically accelerate the biochemical reactions that lead to glycation inside the body, eating foods that are cooked with high heat adds food-derived glycotoxins, which further adds fuel to the fire in terms of glycation. Cooking meats at high temperatures also creates other health hazards, such as the formation of gene-mutating toxins—carcinogens—that significantly increase the risk of cancer.
Cooking with liquids, for example steaming or poaching, inhibits the non-enzymatic attachment of sugar and fat to proteins. “The idea that how I cook my food can have such a tremendous impact on my diabetes is just incredible to me,” says Jean, a 51-year-old court clerk. “I was so excited when I learned about glycation and glycotoxins, and how broiling, barbecuing, and grilling are damaging my health. It was enough to make me change how I cook and what I order when I eat out, and now I feel much more in control of my diabetes and my life.”
Following an anti-glycation eating plan when dining out is easy!
One tip is to always verify how a particular menu item is prepared. If you don’t see what you want, ask if a particular item can be made for you. For example, ask if a grilled fish dish can be poached instead. Request steamed vegetables instead of roasted or grilled vegetables. Choose poached chicken instead of the broiled steak or stir-fried chicken. Here are some other tips to consider when eating out:
What Your Doctor May Not Tell You About Diabetes also provides details of specific nutrients that can help prevent the damage caused by glycation.
To help protect yourself against the damaging consequences of glycation, there is one supplement that is especially important: benfotiamine. Few people have heard about this special variation of vitamin B1 that has been shown to prevent nerve and blood vessel damage—and the resulting complications—that are caused by glycation. What Your Doctor May Not Tell You About Diabetes highlights many experimental studies that show the benefit of benfotiamine in relieving pain due to the nerve and inflammatory damage wrought by glycation, helping alleviate oxidative damage, and preventing glycation-induced damage to the all-important endothelium in blood vessels. One example is a recent study that shows how benfotiamine significantly improves blood flow and reduces oxidative stress in patients who are given meals high in food-derived glycotoxins.
What Your Doctor May Not Tell You About Diabetes also presents a study recently published in Diabetes Care that points to the amazing effect of benfotiamine in preventing glycotoxin-induced inflammation, endothelial dysfunction in the vascular system, and oxidative stress in human patients. In this important study, patients were given a heat-processed test meal with a high level of dietary glycotoxins and then supplemented with 1,050 mg of benfotiamine daily. Benfotiamine significantly reduced glycotoxin-induced damage to the vascular system in these patients. Yet another impressive study in patients with painful peripheral neuropathy shows that 100 mg of benfotiamine given four times daily significantly improves neuropathy scores, with the greatest effect being a reduction in pain in these patients. This recent study confirms the results of a 1999 study, which showed significant improvements in neuropathy scores after only three weeks in patients suffering from painful peripheral diabetic neuropathy. These patients received up to 320 mg of benfotiamine daily, with greater benefits seen in the high-dose group.
Benfotiamine provides tremendous benefit by stopping the accumulation of sugar-derived compounds called triosephosphates that can damage blood and nerve cells. Benfotiamine also activates a key enzyme called transketolase, which renders these triosephosphates harmless, thus inhibiting the damaging action of glycation.
Benfotiamine supplementation therefore holds promising potential for patients who have diabetic neuropathy, diabetic retinopathy, and kidney disease and no side effects have been reported from its use.
Another important supplement for protecting against glycation-induced damage is carnosine. Carnosine is a molecule (dipeptide) composed of two amino acids—beta-alanine and histidine. Carnosine is valuable because it helps inhibit accelerated aging by interfering with glycation, thus protecting against glycation-induced damage and acting as an anti-oxidant to fight oxidative stress.
By binding to protein molecules, carnosine acts as a shield against sugar molecules, thus preventing glycation. Carnosine can also stimulate enzymes and other substances to eliminate damaged, glycated protein, thus helping to reduce the impact of diabetic complications. Evidence of carnosine’s anti-glycation abilities has emerged from several studies. In one recent example involving human cells, carnosine was shown to protect kidney cells against damage from high glucose levels. In another, investigators noted that carnosine and its two precursors—beta-alanine and histidine—may help inhibit the development of atherosclerosis caused by high levels of glycation in diabetes. When carnosine was compared with the anti-glycating drug aminoguanidine in cell culture studies, the supplement proved to be as effective, probably because it inhibits glycation earlier in the process than the drug does.
While healthy people usually take 1,000 mg a day of carnosine in two divided doses (500 mg two times daily), diabetics may consider taking 1,000 mg of carnosine two to three times a day.
As we age, all of us face an onslaught of damage from oxidative stress and glycation. Whether you have diabetes, want to prevent diabetes, or want to minimize the age-accelerating impact upon your body from free-radical damage and glycation, What Your Doctor May Not Tell You About Diabetes provides a wealth of information including a comprehensive, integrated plan that includes nutritional supplements, an anti-glycation eating plan, pharmacologic options (when appropriate), and lifestyle modification to help you combat several insidious factors of aging to live healthier and longer.
Steven Joyal, MD, is the Vice President of Scientific Affairs at the Life Extension Foundation.
If you have any questions on the scientific content ofthis article, please call a Life Extension Health Advisor at 1-800-226-2370.