The Three Major Food Classes
Food consists of elements that belong to four major classes, three of which are Carbohydrates, Proteins, and Fats. Each meal needs to have a balance of the three, along with dietary fibers and vitamins.
Generally, the best way to give your body what it needs is to eat a large variety of foods. Here are specific explanations and guidelines:
- Carbohydrates are composed of a combination of starches, sugar, and fiber. They are broken down by the body and used as an energy source, providing it the fuel it needs for physical activity and proper organ function. They are an important part of a healthy diet, but some kinds of carbohydrates are far better than others.
- "Bad carbs" consist of processed grains that make cooking fast and easy. These easily digested carbohydrates, such as white bread, white rice, pastries, sugared sodas, may contribute to weight gain, interfere with weight loss, and promote diabetes and heart disease.
- Good carbs can’t be digested as easily. This keeps your blood sugar and insulin levels from rising and falling too quickly, helping you feel full quicker and longer. The best sources of carbohydrates are whole grains, vegetables, fruits and beans. They contain vitamins, minerals, fibers, and other important elements.
- Fiber
- Healthy diets rich in whole grains, beans, vegetables, and fruits, usually provide enough fiber, yet most of us only get about half the recommened amounts (20g daily for a grown woman, 30g for a man).Fibers support a healthy diet by:
- Making you feel fuller faster and for longer periods, which can help prevent overeating by maintaining even sugar levels and slowing digestion and absorption.
- Keeping your colon healthy with the organic acids it produces when broken down in digestion.
- Protein - Our bodies need protein to maintain our cells, tissues, and organs. A lack of protein in our diets can slow growth, reduced muscle mass, lower immunity, and weaken the heart and respiratory systems. Protein gives us the energy to be active.
- Complete proteins, such as meat, poultry, fish, milk, eggs, and cheese, provide all of the essential amino acids. An incomplete protein is one that is low in one or more of the essential amino acids. Eating a variety of foods will ensure that you get all of the amino acids you need.
- Animal protein and vegetable protein probably have the same effects on health. When choosing protein-rich foods, pay attention to what comes along with the protein (the amount of fat, especially saturated). Vegetable sources of protein, such as beans, nuts, and whole grains, are excellent choices, and they offer healthy fiber, vitamins and minerals. The best animal protein choices are fish and poultry
- Fats - The type of fat you choose is just as important as how much fat you consume. Also, the biggest influence on blood cholesterol level is the mix of fats in your diet - not the amount of cholesterol you eat from food. That's why it's important to learn about good and bad fats:
- Bad Fats (Saturated and Trans) increase the risk for certain diseases. Saturated fats, primarily found in animal (red meat and whole milk dairy products), raise the bad cholesterol. Choose lean meats, such as skinless poultry, and nonfat or low-fat or nonfat dairy products, as well as fish, and nuts. Tans fats raise bad cholesterol levels and lower good cholesterol. Primary sources of trans fat are certain margarines, crackers, candies, cookies, snack foods, fried foods, baked goods, and other processed foods. Look for trans free foods.
- Good Fats(Monounsaturated and Polyunsaturated) actually lower disease risk according to the Harvard School of Public Health. Primary sources of Monounsaturated fats are plant oils like canola oil, peanut oil, and olive oil. Other good sources are avocados; nuts such as almonds, hazelnuts, and pecans; and seeds such as pumpkin and sesame seeds. Polyunsaturated fats include Omega-3 fatty acids which our bodies can’t produce and are found primarily in cold water fatty fish and fish oils, as well as sunflowers, corn, soybean, and flaxseed oils, and walnuts.
- USDA recommendations:
- Keep total fat intake at about 20-35% of calories
- Limit saturated fats to less than 10% of your calories (200 calories for a 2000 calorie diet).
- Limit trans fats to 1% of calories (2 grams per day for a 2000 calorie diet)
- Limit cholesterol to 300 mg per day, less if you have diabetes.