What Are the Consequences of Over-Nutrition?
Connie Yeung, HK BioTek Intern
Generally speaking, over-nutrition is a form of malnutrition in which nutrients and food are oversupplied to the body. The amount of nutrients consumed exceeds the amount required for normal growth, development and metabolism, so our body health is adversely affected.
Over-nutrition as a global health concern
Over-nutrition, together with hunger, are global health issues that need to be addressed as top priorities. According to the World Health Organization (WHO), more than 1.9 billion adults were overweight and more than 600 million adults were obese whereas 42 million children were overweight or obese in 2014. The WHO also added that childhood obesity is a serious threat to public health.
The general public may have a perception that only developed nations will face the challenges brought by over-nutrition. Yet, it is not the case. The WHO precisely pointed out that the phenomenon of over-nutrition has become more frequent in countries where hunger and under-nutrition are prevalent. Hence, over-nutrition is a growing problem worldwide.
Relationship between over-nutrition and chronic diseases
Diseases like (A) obesity, (B) cardiovascular disease and stroke, and (C) hypertension are associated with poor diet and lifestyle.
A. Over-nutrition and obesity
Defining obesity with body mass index (BMI) is one of the approaches in understanding this health problem. BMI is calculated by weight in kilograms divided by height in meters squared. Below is a table showing how BMI is related to obesity.
Obviously, if the BMI of a person is above 30.0, he/she suffers from obesity. The higher the BMI, the more severe the problem is.
Over-nutrition is highly associated with obesity, especially when the person has a low physical activity level. Our body gains weight when the energy input is higher than the energy output. The energy balance is given by subtracting energy output from energy input. When there is an imbalance of caloric intake of food and caloric expenditure, obesity results.
B. Over-nutrition and atherosclerosis
Atherosclerosis is a common phenomenon in cardiovascular diseases. It occurs when fats, cholesterol and other substances form a plaque which turns into a blood clot on the artery walls, thus restricting blood flow. If it happens in heart arteries like the coronary artery, coronary heart disease can develop and one may experience chest pain and heart attack. On the other hand, if it happens in the arteries leading to the brain, stroke and brain damage are likely to occur.
High cholesterol, an unhealthy diet and obesity are risk factors for cardiovascular diseases, so the negative effects brought by over-nutrition should not be underestimated. Many overweight and obese people have diets that are high in fat, particularly saturated fat. High consumption of fat and cholesterol increases the chance of having blood clots in blood vessels and eventually cardiovascular diseases and stroke can take place.
C. Over-nutrition and hypertension
Hypertension is also known as high blood pressure, which increases the risk for cardiovascular diseases, stroke, renal failure and peripheral vascular diseases. When one’s systolic blood pressure is 120 mmHg or above and diastolic blood pressure is 80 mmHg or above, he/she starts to have hypertension.
This health issue is positively associated to high dietary salt – sodium chloride intake. But how? Literally, sodium in salt brings water into the cells. The extracellular fluid then causes resistance which in turn increases blood pressure. Consequently, high blood pressure happens because of the high salt consumption.
Prevention of over-nutrition related chronic diseases
Isn’t it horrible to know how over-nutrition can cause so many chronic diseases? Don’t worry. Here are the ways that help us fight these enemies!
Prevention is better than cure. First of all, we should increase the intake of food with low Glycemic Index (GI), whole grains, dietary fibers and food that is high in potassium which helps prevent hypertension. After eating low GI food, there will be a slow increase in our blood glucose, followed by a gradual decrease later on. Examples of low GI food are apples, bananas, milk, cheese, etc.. Consumption of meat, saturated fat, trans fat, cholesterol and salt should be reduced accordingly. Changes in lifestyle are also needed. We should do exercises regularly to increase energy expenditure to help lose weight. Last but not the least, we should read nutrition labels before buying any products to learn more about the nutrition facts of the food we are going to eat.
Health is the most important asset to every one of us. Starting from today, let’s adopt a healthy lifestyle together!