Whole grain

[7][8][9] As components of breakfast cereals, whole grains are associated with improved micronutrient intake and lower risk of several diseases.

[11] Cereal proteins have low quality, due to deficiencies in essential amino acids, mainly lysine.

[12][13] Supplementation of cereals with proteins from other food sources (mainly legumes) is commonly used to compensate for this deficiency,[13] since the limitation of a single essential amino acid causes the others to break down and become excreted, which is especially important during the period of growth.

[6][15] Manufacturers of foods containing whole grains in specified amounts are allowed a health claim for marketing purposes in the United States, stating: "low fat diets rich in fiber-containing grain products, fruits, and vegetables may reduce the risk of some types of cancer, a disease associated with many factors" and "diets low in saturated fat and cholesterol and rich in fruits, vegetables, and grain products that contain some types of dietary fiber, particularly soluble fiber, may reduce the risk of heart disease, a disease associated with many factors".

[4][20][10] Regular whole-grain consumption may lower elevated LDL and triglyceride levels, which are risk factors for cardiovascular diseases.

[23] A 2017 review of clinical trials found insufficient evidence for a relationship between whole grain consumption and lowered risk of cardiovascular diseases.

[5][25][26] In genetically susceptible people, gluten (proteins found in wheat, barley, rye, oat, and related species and hybrids)[27] can trigger coeliac disease.

[citation needed] Under the Food and Drug Regulations, up to 5% of the kernel can be removed to help reduce rancidity and prolong the shelf life of whole-wheat flour.