Low free fatty acids are caused by excessive consumption of sugar and fat factors in the body, which is common in diabetes and thyroid system diseases. It may lead to ketoacidosis, and individuals should adjust their dietary habits in a timely manner. The basal metabolic rate in the body of people with hypothyroidism is reduced, and the secretion of various nutrients in the body is lowered, resulting in low free fatty acids. It is common in endocrine system disorders, because the level of hormone content in the body is unstable, resulting in a lower content of various amino acids and proteins in the body, which also affects the content of triglycerides and fat factors in the body.