Try to limit protein intake to lean sources of protein and avoid starches, especially after 5 p.m.

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Overall, protein intake in Europe and America is unlikely to expand much, but a combination of rising incomes and population in developing countries could increase demand by more than 5% annually for years to come.

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Yet despite the differences in protein and fat intake, the level of body fat increased by essentially the same amount among all the participants.

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Regular intake of soy protein and the omega-3 fatty acids in tofu, can reduce cholesterol levels by as much as 30% and LDL (bad cholesterol) by 30%-40%.

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He said dietary intake of carbohydrate and protein is known to promote muscle protein synthesis, he said.

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The diet is high in animal protein, which could lead to an excess intake of saturated fat, resulting in elevated cholesterol levels, an increased risk of heart disease and increased risk of certain types of cancer.

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The main phenylketonuria treatment is a strict diet with very limited intake of phenylalanine, which is mostly found in foods containing protein.

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To keep inflammation to a minimum, Dr. O'Keefe recommends a restricted-calorie diet (similar to the Mediterranean diet), consisting of fruits and vegetables, lean protein, nuts, vinegar, tea, and fish oil, as well as low to moderate alcohol intake.

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