Components of Food
If you are trying to make heart-healthy changes to your lifestyle and diet, it's helpful to know some basics about nutrition, starting with the components of food.
Facts about calories
You need enough calories to give you energy, but no more than you can burn off. This is called an energy balance.
If you take in more calories than you burn, you gain weight.
If you take in fewer calories than you burn, you lose weight.
If you balance the two, you maintain your weight.
Even when you are working on weight loss, you shouldn't cut back calories so much that you don't meet your energy needs. The number of calories you need depends on your age, gender, and activity level.
- A great way to get a personalized estimate of your calorie and nutrient needs for your health goals is to speak with a registered dietitian.
Facts about dietary cholesterol
Remember that "cholesterol-free" does not mean "fat-free."
Dietary cholesterol is a fat-like substance found in all foods from animals. This includes egg yolks, meat, poultry, fish, milk, and milk products.
- Dietary cholesterol doesn't seem to have as big of an impact on blood cholesterol as once thought. But if you have high cholesterol, always talk with your healthcare provider or registered dietitian to see what they advise for you.
- Your liver makes all the cholesterol you need. Foods high in saturated and trans fats cause your liver to make more cholesterol than it otherwise would. That's why it's important to limit these types of foods.
Types of fats
Fatty acids are the basic chemicals in fat. They may be saturated, polyunsaturated, monounsaturated, or trans fats. These fatty acids differ in their chemical makeup and structure, and in the way in which they affect your blood cholesterol levels.
Is used by the liver to manufacture cholesterol
Can raise blood cholesterol levels, particularly the LDL ("bad") cholesterol level (this raises your risk for heart attack and stroke)
Should make up no more than 10% of your daily calories
Saturated fat can be found in meats, whole dairy products, butter, cocoa butter, coconut, and palm oils.
Don't appear to raise blood cholesterol levels
Examples of polyunsaturated fats include safflower, sunflower, and corn oils, and soybean oils.
Don't seem to raise bad cholesterol levels. They may help boost HDL ("good") cholesterol in the blood. Higher HDL levels have been linked to a lower risk for heart disease.
Examples of monounsaturated fats include olive and canola oils.
Trans fat is found naturally in some animal foods. Trans fats can also be made by food manufacturers. These are byproducts of hydrogenation. This is a chemical process used to change liquid unsaturated fat to a more solid fat. Trans fats will be found in an ingredients list as a partially hydrogenated oil. Trans fatty acids are similar in structure to saturated fat. They may have a great impact on raising total cholesterol and LDL cholesterol levels. You should avoid trans fats as much as possible.
The FDA has banned manufacturers from adding artificial trans fats, or partially hydrogenated oils, to food.
Examples of foods that had trans fats include stick margarine and fats found in commercially prepared cakes, cookies, and snack foods. Many manufacturers have changed their formulas to no longer contain trans fat. Read the label to make sure the food has no partially hydrogenated oils in the ingredients list.
Facts about fats
All fats contain about the same number of calories teaspoon for teaspoon. There is no such thing as low-fat fat.
Fat is the most concentrated source of calories. It supplies more than twice as many calories per gram as either carbohydrates or proteins (9 calories per gram compared with 4 calories per gram).
- Your total fat intake should be no more than 30% of your daily calories.
Most people get too much fat in their diet. This adds to health problems, like obesity, high blood cholesterol, and heart disease.
Coconut and palm oils have no cholesterol, but they are high in saturated fat. You should avoid these fats.
Facts about fiber
- Fiber is a type of carbohydrate found in plant foods, such as fruits, vegetables, whole grains, and legumes.
- Fiber slows down how quickly foods are digested, making you feel full longer after eating.
Your body doesn't digest most of the fiber you eat. Fiber can be soluble or insoluble.
Soluble fiber is found in foods like oat bran and dried beans. It can lower blood cholesterol in some people. It prevents some fats and cholesterol from being digested and absorbed.
Insoluble fiber is found in foods like wheat bran. It increases bulk in the digestive tract, improving frequency of bowel movements. It does not help lower cholesterol.
Facts about sodium
Salt is the main source of sodium in most people's diets.
Sodium and salt are not the same. A teaspoon of table salt contains 2,300 milligrams of sodium.
Sodium is a mineral needed to keep body fluids at a healthy level. It's also important for nerve function. It's found naturally in some foods, but most of the sodium in the average diet comes from seasonings and ingredients added to foods.
You need some sodium for good health, but most people get more than they need. In some people, too much sodium in the diet can raise blood pressure. This raises the risk for heart disease and stroke.