Whole grains: A good dietary choice to stay healthy

 

According to the degree of processing, grains can be divided into refined grains and whole grains.

 

Whole grains refer to cereal grains that have been cleaned but have had no further processing that would change the complete grain structure, as well as grain products that have been milled and crushed, but the proportions of bran, endosperm, and germ are the same as those of intact grains.

 

Common whole grains include millet, corn, oats, buckwheat and whole wheat. Compared with refined grains, whole grains contain more nutrients such as B vitamins, minerals and dietary fiber. Refined grains only retain the high-starch endosperm, resulting in the loss of nutritional value.

 

According to the 2022 Dietary Guidelines for Chinese Residents, there is sufficient evidence that shows it's beneficial to increase the intake of whole grains.

 

1. Reducing the risk of all-cause mortality

 

Compared with low-intake groups, high-intake groups of whole grains cut the risk of all-cause mortality by 12 percent. As the average daily intake of whole grains increases by 30g, the risk of all-cause death will decrease by 8 percent; when the intake reaches 100g per day, the risk can be reduced by 25 percent.

 

2. Reducing the risk of Type 2 diabetes

 

The digestion and absorption rate of whole grains is slower than that of refined grains, which can delay the absorption of glucose, help control blood sugar, improve insulin sensitivity and reduce the risk of diabetes. 

 

Studies have shown that consuming 48 to 80 grams of whole grains per day is associated with a 26-percent decrease in the risk of developing Type 2 diabetes, compared to people who consume small amounts of whole grains.

 

3. Reducing the risk of cardiovascular disease

 

Replacing refined grains with whole grains can help lower the levels of total cholesterol, LDL cholesterol and triglycerides in the blood. A daily intake of 48 to 80g of whole grains can mitigate the risk of cardiovascular disease by 21 percent.

 

4. Maintaining a healthy weight 

 

Whole grains are rich in dietary fiber, which can enhance satiety and thus cut the intake of other foods. Eating whole grains is therefore helpful in weight control. 

 

When the average daily intake of whole grains reaches 48g or more, BMI can be reduced by 0.63kg/m2, and waist circumference can be trimmed by 2.7cm. Increasing the intake of whole grains can lower the risk of weight gain by 17 percent.

 

According to the 2022 Dietary Guidelines for Chinese Residents, adults are advised to consume 200 to 300g of grains per day, including 50 to 150g of whole grains and miscellaneous beans.

 

To achieve the recommended intake of whole grains, at least one of the three meals in a day should contain whole grains or beans. One can add whole grains while making rice or porridge, mix corn flour or whole wheat flour into wheat flour when making wheaten food, or simply choose buckwheat noodles, whole grain bread, oatmeal, and other foods that are high in whole grain content.

 

1. People with emaciation, anemia and calcium deficiency

 

Whole grains are rich in dietary fiber, excessive intake of which will speed up gastrointestinal emptying, making food pass through the gastrointestinal tract too fast and resulting in a lower digestion and absorption rate of protein. Moreover, the phytic acid and oxalic acid in whole grains will affect the body's absorption and utilization of iron, zinc, magnesium, calcium and other minerals.

 

2. The elderly and children prone to indigestion

 

The elderly and young children are recommended to eat a soft diet to reduce food irritation and damage to the gastrointestinal tract. Whole grains can be made into soft rice or multigrain porridge or steamed sponge cakes before being served to these groups.

 

3. Patients with gastric ulcers, gastroesophageal reflux, intestinal bleeding and other gastrointestinal conditions

 

People suffering from such conditions are not recommended to eat whole grains. They should follow the doctor's advice on dietary choices.