Foods are categorized into three groups, the fat, the protein and the carbohydrate.
1 g fat equals to 9 calories. It doesn’t matter whether it is good fat (unsaturated, such as olive oil, canola oil, fish oil, cod liver oil, and peanut oil) or bad fat (saturated, such as lard, butter, hydrogenate oil and coconut oil). Saturated fat stays solid at room temperature while unsaturated fat stays liquid at room temperature. Canola oil is recommended as a No.1 cooking oil because it is high in monounsaturated fat, inexpensive and high in burning point. Oil with low burning point can break down to carcinogens easily when heated. Olive oil is recommended as a No.1 salad oil because it is high in monounsaturated fat, and low in burning point. Peanut oil and cotton seed oil are not recommended anymore because they are high in polyunsaturated fat, which potentially increase the risk of inflammation, people with chronic pain and arthritis should avoid them. Fish oil is high in omega-3 fatty acid, which is good for the heart. Do make sure the fish oil supplement is cholesterol free. Garlic and vinegar can soften the blood vessels and reduce cholesterol level. Current recommendation from American Dietetic Association are limit saturated fat to <10% of total calories; Intake of trans (hydrogenate) fat should be minimized; In individuals with diabetes, limit dietary cholesterol to <200 mg/day; two or more servings of fish per week (with the exception of commercially fried fish filets) provide omega-3 polyunsaturated fatty acids and are recommended.
1 g of protein equals to 4 calories. It doesn’t matter whether it is high biological value protein (usually seen in animal originated protein, such as egg, chicken, turkey, beef, pork, and lamb) or low biological value protein (usually seen in plant-based protein, such as soy, beans, and legums). People with compromised kidney function should consider eating more high biological value protein. Reduction of protein intake to 0.8–1.0 g · kg body wt–1 · day–1 in individuals with diabetes and the earlier stages of Chronic Kidney Disease (CKD) and to 0.6 g · kg body wt–1 · day–1 in the later stages of CKD improve measures of renal function. A healthy adult only needs 50-60 g protein, about 7-8 oz per day. Over consumption of protein bring extra burden to the liver and kidney, increase the risk of osteoporosis, and increase the risk of imbalanced body acid-base. High-protein diets are not recommended as a method for weight loss at this time. The long-term effects of protein intake >20% of calories on diabetes management and its complications are unknown.
1 g of carbohydrate equals to 4 calories. It doesn’t matter whether it is simple carbohydrate (mainly added sugars, which have very little nutritional value. They are considered "empty" calories. Types of simple carbs are soda, candies, cookies, high fructose corn syrup, etc. Fruit is also considered a simple carb, but it is a naturally occurring sugar that is packed with many nutrients) or complex carbohydrate (whole grains take a while to absorb, resulting in a steady blood sugar levels, which allows you to feel "full" longer and gives you lasting energy. Whole grains are packed with nutrients, especially fiber). A dietary pattern that includes carbohydrate from fruits, vegetables, whole grains, legumes, and low-fat milk is encouraged; low-carbohydrate diets, restricting total carbohydrate to <130 g/day, are not recommended in the management of diabetes & overweight/obesity; there is not sufficient, consistent information to conclude that low–glycemic load diets reduce the risk for diabetes. Nevertheless, low–glycemic index foods that are rich in fiber and other important nutrients are to be encouraged.
In summary, individuals with chronic illness, such as diabetes, overweight/obesity, high cholesterol, high blood pressure, and heart diseases are encouraged to implement lifestyle modifications that reduce intakes of energy, saturated and trans fatty acids, cholesterol, and sodium and to increase physical activity (exercise 150 min./wk) in an effort to improve glycemia, dyslipidemia, blood pressure and weight loss.