Whole grain cereals and foods can reduce the risk of certain diseases, including coronary heart disease, colon cancer, diabetes and diverticular disease. Common cereals include bread, breakfast cereals, rice and pasta.
Grains, Whole Grains, and Types of Grains
Grains include wheat, barley, oats, rye, corn, rice, millet, and triticale. Whole grains include whole wheat or whole wheat bread or crackers, dark “seed” bread, whole grain breakfast cereals, wheat germ, brown rice, puffed whole grains, bulgur, quinoa, couscous, popcorn, and oatmeal.
Refined grains include cakes, desserts, white bread, pasta, muffins, sweet or savory cookies, refined grain breakfast cereals, white rice, pancakes, waffles and pizza.
Nutritional Facts of Whole Wheat Cereals
Whole grains are made up of three main parts, including:
Bran – the outer layer of a grain that contains fiber, omega-3 fatty acids, vitamins and minerals
Endosperm – the main part of the grain, containing mainly starch
Germ – the smallest part of a grain that contains vitamin E, folate, thiamine, phosphorus and magnesium
Whole grain cereal benefits
Whole grain cereals are a rich source of many essential vitamins, minerals, and phytochemicals (compounds found in plant foods that have significant health benefits). Typical whole grain cereals are:
Low in saturated fat but a source of polyunsaturated fats, including omega-3 linolenic acid
Cholesterol free
Rich in soluble and insoluble fiber and resistant starch
Excellent source of carbohydrates
Great source of protein
Good source of B vitamins including folate
Is a good source of many minerals such as iron, magnesium, copper, phosphorus and zinc
A good source of antioxidants and phytochemicals that help lower blood cholesterol levels.
Protective chemicals in whole grains
Whole grain cereals contain many different phytochemicals that have been linked to significant health benefits). These phytochemicals include:
Lignans – May reduce the risk of coronary heart disease and slow or reverse cancer in animals
Phytic acid – lowers the glycemic index (GI) of foods. This may be important for people with diabetes and help prevent the development of colon cancer cells
Saponins, phytosterols, squalene, oryzanol, and tocotrienols – have been found to lower blood cholesterol
Phenolic compounds – have antioxidant properties.
When whole grains are refined
When grains are refined (for example, to produce white flour), the bran and germ layers are usually removed, leaving only the endosperm. This process results in a significant loss of fiber, vitamins, minerals, antioxidants and phytochemicals in the grain.
Some fiber, vitamins and minerals can be added back to refined grain products (such as white bread) to compensate for losses, but it is not possible to add the mixture of phytochemicals lost during processing. In Australia, wheat flour used to make bread must have folic acid and thiamine added, and salt must be iodized.
Refined grains often have high levels of added sugar, fat, or salt, and often have a higher glycemic index than whole grain grains. Eating excess amounts of refined grains can cause sharp spikes in blood sugar levels and a strong reaction in the pancreas, which over time, combined with other unhealthy eating behaviors, can lead to the development of diabetes.
Whole grains help prevent heart disease
Eating whole-grain cereals (especially those containing oat or barley fiber) has been linked to a protective effect against heart disease in adults. Studies show that high intake of whole grains (at least 2.5 servings per day) reduces the risk of cardiovascular events. Additionally, a study of postmenopausal women found that eating six or more servings of whole grains per week may protect against the effects of cardiovascular disease.
One contributing factor to heart disease is high blood cholesterol levels. Studies have found that regular consumption of whole grain cereals rich in soluble fiber, such as oats (containing beta-glucan) and psyllium, can significantly lower blood cholesterol levels and may prevent the development of heart disease.
Whole grains and type 2 diabetes
Results from the Nurses’ Health Study I and II show that eating two servings of whole grain cereals a day can reduce the risk of type 2 diabetes by 21 percent. The fiber in whole grain cereals, in particular, can prevent this from happening. People with diabetes may also benefit from consuming whole-grain cereals, which have been linked to improved insulin sensitivity and better diabetes control.
Whole grains and weight management
People who are overweight or obese tend to have energy-dense diets. High-fiber foods, such as whole-wheat breads and cereals, can be an effective part of any weight loss plan because they tend to be less energy dense. This means they provide fewer calories per gram of food. High-fiber foods take longer to digest and create a feeling of fullness, which can prevent overeating. Whole grains are naturally lower in saturated fat and contain healthier polyunsaturated fatty acids.
Whole grains, cereals and gut health
High-fiber foods, such as whole-grain cereal products, increase the movement of food through the digestive tract. The result is increased stool volume, softer, larger stools, and more frequent bowel movements. This provides a favorable environment for beneficial gut bacteria while reducing levels of damaging bacteria and the build-up of carcinogenic compounds. Wheat fiber can bind certain toxins and remove them from the stool in the large intestine.
A high-fiber diet, especially one high in insoluble fiber, may reduce the risk of colon cancer and diverticulosis (a disease in which “pouches” form in the intestinal wall).
Whole grain cereals and cancer
Eating one to three servings of fiber-rich whole grain cereals per day may reduce the risk of colorectal cancer in adults. Three servings of whole grains (about 90 grams) a day may reduce the risk of colorectal cancer by 20 percent, and the risk may be reduced even further if more whole grains are consumed.
Whole grain cereals recommended for health
Whole grain cereals are recommended as part of a healthy diet. The Australian Guide to Healthy Eating recommends adults aged 19-50 eat six servings of cereals a day, the majority of which should be wholegrain. Men and women aged 51 to 70 should consume at least six and four servings of grains, respectively.
Adults 70 years and older should consume at least 4.5 servings of grains for men and 3 servings for women. The recommended intake for children and adolescents depends on their age and gender.
