Nov. 14, 2002 - Cooking food slowly and at a low temperature may reduce the risk of heart disease, especially in people with diabetes. Simmering food appears to limit the development of chemicals in food that drive up blood levels of heart- and vessel-harming substances, finds a study in this week's Proceedings of the National Academy of Sciences.
Researchers from Mount Sinai School of Medicine in New York found that diabetics had less of these harmful substances, called advanced glycation end products, or AGEs, when food was cooked slowly and at a low temperature than when they ate foods cooked at high temperatures. As a result, they had fewer blood chemicals associated with heart disease.
AGEs are a byproduct of the cooking process. High temperatures scorch the natural sugars found in food, creating harmful chemicals. Not only have high levels of AGEs been implicated in cardiovascular disease, they may also interfere with the body's ability to heal wounds, a problem many diabetics deal with on a regular basis.
In the study, 24 people with diabetes were fed two nutritionally similar diets, both approved by the American Diabetes Association. The only difference is that one of the diets was designed to provide five times fewer AGEs by cooking food slowly and at low temperatures.
Thirteen of the diabetic participants spent six weeks on either the low-AGE diet (7 people) or the high-AGE diet (6 people) and 11 other diabetic participants spent two weeks on one diet with a "washout" period of one to two weeks and then two weeks on the alternate diet.
Diabetics on a two-week, high-AGE diet increased their blood level of these harmful substances by 65%. But after a "washout period" and then two weeks on a low-AGE diet, their blood level of these harmful substances dropped by 30%. Those who ate a high-AGE diet for six weeks increased their AGE levels by 28%. A low-AGE diet for six weeks decreased these substances by 40%.
The researchers also found that eating diets low in AGEs reduced the level of other potentially harmful substances in the blood, including LDL cholesterol ("bad cholesterol"). During the two-week, low-AGE, diabetics had lower LDL levels than those on a high-AGE diet. A six-week, low-AGE diet caused a 33% reduction of LDL, while a high-AGE diet increased LDL by 32%.
Low-AGE diets also led to declines in chemicals linked to blood vessel damage.
The study found similar abnormalities in another inflammatory marker known to be associated with heart disease in patients on the diets high in AGEs. Heart disease is the number one killer of diabetics.
SOURCE: Proceedings of the National Academy of Sciences, Nov. 12, 2002.