Is obesity genetic?
Many things can cause you to gain weight, but is obesity genetic? Learn about the relationship between genetics and obesity and what research can tell us.
Obesity is a complex disease and weight management often comes with a lot of questions.
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On one hand, obesity is a heterogenous disease, meaning it is different in everyone. Understanding this is important, as it can explain why your body may act differently to someone else’s who may be managing their weight in the same way.
On the other, the weight loss pattern experienced by people who are trying to lose weight, has been found to be incredibly similar and predictable. Most people start by losing a large amount of their body weight quickly. This is then followed by a period of plateau, where the rate of weight loss slows down considerably.
Before trying to understand why your weight loss could be slowing down and 'plateauing’, it can be beneficial to learn the biology behind obesity. In a simple way, our bodies need energy to keep us alive. We get this from the food that we eat, some of which our body stores as fat. The rate at which our body uses this extra fat depends on several elements – behavioural and environmental are often quoted as the most common – but in reality, there are also other complex factors at play.
The connection between obesity and these complex factors influences why weight loss is often not linear, i.e., why you may experience ‘ups and downs’ in your weight management journey.
So, what other factors could be influencing the rate at which you lose weight?
Did you know, obesity is genetic for 40-70% of people living with the disease? Your genes can determine how your brain and central nervous system (CNS) sends and receives signals that indicate positive feelings after you eat - whether you feel full and satisfied. Your genetics can also determine how your body will react to environmental factors – this is called your phenotypes, and is currently a big focus of research for obesity specialists. An example of this is whether or not you carry extra weight around your stomach.
For most people, obesity is caused by the development of multiple genes that work together to increase the likelihood of obesity in an individual, rather than a single gene mutation.
The signals your brain receives to indicate feelings of hunger and feeling full are dictated by hormones in different parts of your body. For example, hormones in the stomach (Ghrelin) exhibit feelings of hunger, whereas hormones in your fat cells (Leptin) control or inhibit feelings of hunger.
For some people living with obesity, the Leptin hormone doesn’t work properly, leading to an increase in feelings of hunger.
Regardless of the intensity of a weight loss effort, many people will experience a period of plateau on their journey. Without proper support, this can be demotivating and hard to understand.
When a weight management journey starts, it is usually recommended to reduce the number of calories you consume. A reduction in calorie intake can lead to a significant amount of initial weight loss, especially when paired with physical activity. For people living with overweight and obesity, this is recommended to be regular brisk walks, four times a week.
As you continue your journey, you may find the rate of your weight loss does not remain at this level. In fact, for most, weight loss plateaus and you may even experience weight gain. This is all to do with your hormones.
As you reduce calorie intake, the amount of energy it takes to lose weight decreases at a lower rate. In addition, level of hunger you feel (your appetite) increases. This means that the more weight you lose, the stronger the signals are to your brain that make you feel hungry. In essence, weight loss triggers internal hormone changes that encourage weight regain. Understandably, this can make a person feel like they’re fighting an uphill battle.
The good news is that with the right weight management team, the weight plateau can be overcome. Explore this site for support on how to have the right conversations with your healthcare team.