What Factors Influence Body Weight? Here’s What Everyone in Nutrition and Health Programs Should Know

When thinking of things that influence a person’s body weight, the first things that probably come to mind are eating habits and exercise regimens. Though both these things do indeed factor into a person’s body weight, the overall picture is more complex. 

Food-related habits, like the consumption of high-fat and high-calorie foods, and the speed at which a person eats, can influence body weight. Exercise, or the lack of it, is also a determinant of body weight. However, there are many factors that come together to determine a person’s body weight, and not all of them are related to lifestyle choices.

Body weight is a combination of fate and free will, nature and nurture. It’s important for students in nutrition and health training to understand this in depth. Read on for more information. 

Genetic Determinants Affecting Body Weight 

Some of the factors that influence how much a person weights cannot be changed, like certain genetic determinants. Here are some facts about the relationship between genes and body weight: 

  • A person’s genes set the basic parameters on how efficient their metabolism is
  • The metabolism is the efficiency with which the body burns calories 
  • The more efficient the metabolism, the less energy it requires to run 
  • Excess energy is stored in the body as fat 
  • People who are overweight tend to have more efficient metabolisms 

Nutritionist giving consultation to patient with healthy fruit and vegetable, Right nutrition and diet concept

Besides metabolism, genes may also affect where on the body extra fat is stored. It’s important to note that the genes governing a person’s metabolism only set into place a tendency towards a certain metabolic efficiency. They don’t fully determine it, and metabolic efficiency is influenced by many other factors, including lifestyle. 

The Link Between Age and Body Weight 

Another factor unrelated to personal agency is the age of an individual. Graduates of nutrition and health programs know that age intersects with body weight in two different ways: 

  • Certain developmental factors are central in determining a person’s body weight 
  • People tend to gain weight as they age

There are three different developmental periods that are key influences on a person’s overall body weight. The prenatal period, the period in childhood between 5 and 7 years old, and the period of adolescence. How a person engages with food, eating habits, stress, and energy expenditure during this time influences their lifetime body weight. 

As we age, we tend to gain body weight as our metabolism slows

Many people also gain weight as they age. Every ten years after our mid-twenties, our metabolism slows down by around 10%. Inactivity and the aging process accelerate the loss of muscle tissue, decreasing metabolic efficiency. 

Professionals with a Diploma in Nutrition Understand the Effects of Geographical Location 

A factor influencing body weight that many don’t think about is geographical location. Experts with nutrition and health training know that living in a neighbourhood that has accessible and plentiful grocery stores, as well as many green spaces that are safe for physical activity, impacts body weight. 

A person living in a neighbourhood without access to healthy food may have a higher body weight

Food deserts are a major issue causing many health problems for the populations that live in them. These are areas without easy access to nutritious, inexpensive food, and are found mainly in:

  • Low-income communities 
  • Rural communities 
  • Indigenous reservations 
  • Northern communities 

In these areas, the lack of grocery stores is usually coupled with easy access to fast-food restaurants. The energy-dense, micronutrient-lacking food in these stores contributes to health problems and tends to skew body weight heavier. 

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