In men with overweight or obesity, eating a single meal high in fat leads to higher levels of triglycerides and homocysteine in the blood after eating than eating a meal with the same number of calories but high in carbohydrates.

Men who have overweight or obesity tend to have higher levels of triglycerides in their blood after fasting and after eating, compared to men with normal body weight, no matter whether they eat a meal high in fat or high in carbohydrates.

For adults with cardiometabolic risk factors, eating a meal with 50 grams of fat leads to lower attention after eating and greater feelings of hunger compared to eating a meal with 25 grams of fat, even when both meals have the same number of calories.

Men who are overweight or obese tend to have higher levels of homocysteine in their blood after an overnight fast compared to men with normal weight. Eating meals high in fat or carbohydrates causes homocysteine levels to rise further in the hours after eating.

Eating a high-fat meal before exercising raises levels of free fatty acids in the blood of both lean and obese men, but does not change the levels of the stress hormones epinephrine and norepinephrine in the bloodstream.

When people eat less fat and more carbs, their blood fat levels (triglycerides) go up a lot—even if their cholesterol stays the same—and high blood fat is linked to heart disease.