Genetic Factors in Obesity: What You Can and Can not Change

Introduction

Environmental, lifestyle, and genetic factors all have an impact on obesity. How quickly you burn calories, how much fat your body stores, and how hungry or full you feel can all be influenced by your genes. Some people may be more likely than others to gain weight due to these inherited characteristics.

Genetics, however, is not fate. Although you cannot alter the genes you are born with, you can alter several factors that affect how those genes function, including stress levels, physical activity, sleep patterns, and diet. Despite genetic risks, knowing the role of genetics enables you to concentrate on what you can control and make healthier decisions.

Recognizing the role of genetic factors in obesity

Obesity is most likely largely caused by genes. Appetite control, metabolism, food cravings, fat distribution, and energy expenditure are all impacted by its composition.

• Hormone levels that control hunger and satiety can be changed by certain gene variations, which can make people feel less satisfied or more hungry after eating.
• Metabolism: The basal metabolic rate, which determines how effectively fat is burned while at rest, is influenced by genetics.
• Fat distribution: Hereditary factors can also affect the distribution of fat, especially in high-risk areas like the abdomen.

Genetic factors contribute to obesity

Many aspects of weight issues are significantly influenced by genes. These factors may include energy expenditure, fat distribution, metabolic rate, and appetite control.

• Hunger hormones: Our hunger hormones, ghrelin and leptin, send out signals about hunger and fullness. On the other hand, weight gain may result from specific genetic variations that alter hormonal signaling pathways.
• Excessive fat accumulation: Enzymes linked to lipid metabolism can be impacted by genetic changes. Our body’s ability to efficiently process and store fat is also hampered by these modifications. These genetic differences lead to an excessive accumulation of fat cells and an excess of weight.
• Interaction of genetics and environmental Factors: Epigenetic markers and genetic expression patterns can be influenced by environmental factors such as diet, stress, and irregular exercise. Obesity can result from changes in these patterns, which are often linked to metabolic wellness and weight control.
• Healthcare professionals can effectively manage obesity by identifying individuals who may be genetically predisposed to obesity.

Obesity’s Genetic Causes: Polygenic, Monogenic, and Syndromic

Although they can also be monogenic, genetic causes of obesity are typically polygenic. The latter are frequently syndromic and therefore comparatively uncommon due to mutations in a single gene or groups of genes.

Prader-Willi syndrome and fragile X syndrome are two examples. Obesity that is not syndromic may have chromosomal, polygenic, or monogenic origins.

Polygenic Obesity: The Role of Several Genes in Weight Gain

As the name implies, polygenic obesity is caused by several genetic factors. This group includes 60% of genetic cases. Several of these polygenic variants interact with environmental factors to cause obesity.

Obesity is not guaranteed by any of these gene variants. In general, any one of them by itself is regarded as low-risk. Many are also present in people who are not obese. A gene is considered linked to obesity if it is more prevalent in obese people than in non-obese people. Some are more common than others.

FTO’s Function in Obesity

The fat mass and obesity-associated gene (FTO), which is present in as many as 43% of people, is one such gene. People with the fat mass and obesity-associated gene may find it difficult to restrict their caloric intake when food is easily accessible. This gene, along with other genes, can lead to:

• An increase in appetite
• A higher intake of calories
• Diminished appetite and diminished self-control
• An increased propensity for inactivity
• An increased propensity to accumulate body fat

Genome-wide association studies (GWAS) have shown that the FTO allele linked to obesity is prevalent in individuals of European origin. Numerous biological and metabolic processes are affected.

FTO has drawn a lot of attention from researchers as a possible therapeutic target for the treatment of obesity. It has been discovered that a number of micronutrients and small-molecule medications regulate the expression or activity of FTO, which helps to control metabolism.

Monogenic Obesity: Severe Obesity Resulting from a Single Gene

Although monogenic obesity is less prevalent, it may be simpler to detect because it typically affects individuals from an early age. Monogenic obesity is known to be caused by rare, high-risk genetic variations in about two dozen genes. Three major categories comprise the gene mutations associated with monogenic obesity:

• Leptin, leptin receptor, melanocortin-4 receptor, proopiomelanocortin (POMC), and prohormone convertase 1/3 are all physiologically involved in the hypothalamic Leptin-Melanocortin system of energy balance.
• those required for hypothalamic development, such as SIM1, BDNF, and NTRK2. Severe obesity is caused by mutations in these genes.
• those in whom obesity manifests as a component of a complex syndrome, but whose functional relationship to obesity is still unknown.

Extremely high levels of hunger are linked to rare single-gene defects that cause severe obesity starting in early childhood. Those who became severely obese before the age of two should think about consulting an obesity medicine specialist about getting screened for:

• Lack of leptin
• POMC insufficiency
• MC4R insufficiency

Syndromic Obesity: The Connection Between Obesity and Genetic Syndromes

Syndromic obesity is a rare hereditary condition that manifests at birth and is frequently linked to comorbidities. Patients with these conditions may also have organ-specific abnormalities, hyperphagia, dysmorphic features, cognitive delay, and other symptoms of hypothalamic dysfunction in addition to being overweight.

Among the more well-known obesity-related syndromes are the following:

• Prader-Willi syndrome
• Bardei-Bietl syndrome
• Cohen’s syndrome

Treating or managing one of these syndromes would usually differ significantly from treating other forms of obesity. The leptin-melanocortin pathway, a possible target in some types of syndromic obesity, is the subject of ongoing research.

Environmental factors that contribute to obesity

Environmental factors are the external factors that contribute to these issues, whereas genetic factors are the internal forces that cause weight gain and lead to being overweight. They include everything in our surroundings that increases our propensity to overeat or underexercise. When considered collectively, experts believe that environmental factors are the primary cause of obesity and its sharp increase.

Environmental factors start to affect you even before you are born. Researchers sometimes refer to these exposures during pregnancy as “fetal programming.” Compared to babies whose mothers did not smoke, babies whose mothers smoked during pregnancy are more likely to grow up to be overweight.

This also applies to infants born to mothers with diabetes. These conditions, according to researchers, may somehow change the developing baby’s metabolism in ways that manifest later in life. Compared to infants who are breastfed for less than three months after birth, babies who are breastfed for more than three months have a lower chance of becoming obese as teenagers.

People frequently carry over childhood habits into adulthood. Children who consume high-calorie, processed foods and sugary sodas develop a taste for these items, which tends to encourage weight gain as adults. Similarly, children who choose to play video games and watch television rather than engage in physical activity may be setting themselves up for a sedentary future.

Numerous aspects of contemporary life encourage weight gain. To put it briefly, we are encouraged to eat more and exercise less in today’s “obesogenic” environment. Additionally, there is mounting evidence that more general aspects of our lifestyle, like our stress levels, sleep patterns, and other psychological factors, can also have an impact on our weight.

One of the factors contributing to obesity is food

Food is easily accessible almost everywhere we go, including shopping malls, sports arenas, and movie theaters. Roadside rest stops, 24-hour convenience stores, gyms, and health clubs all sell snacks and meals. Spending on food consumed outside the home is significantly increasing among Americans: 46% of our food budget is on food consumed away from home, up from 27% in 1970.

One portion size was available at fast-food establishments. Portion sizes have increased dramatically in recent years, and this trend has affected a wide range of other foods, including sandwiches, steaks, cookies, and popcorn. Three times as many calories are found in a typical McDonald’s French fry serving as there were when the franchise first started. A single “super-sized” meal might have 1,500–2,000 calories, which is more than most people require for a full day. Furthermore, studies reveal that even when they are already satisfied, people frequently eat what is in front of them. It should come as no surprise that we are consuming more high-calorie foods (particularly pizza, soft drinks, and salty snacks), which are far more accessible than lower-calorie options like salads and whole fruits.

Fat isn’t always the issue, in fact our diet’s fat content has decreased. However, because they use a lot of sugar to enhance their flavor and palatability, many low-fat foods are extremely high in calories. In actuality, a lot of low-fat foods have more calories than non-low-fat foods.

Stress and associated problems

Obesity experts now think that various facets of American culture may work together to encourage weight gain. A common thread connecting these elements is stress. Working long hours and taking fewer or shorter vacations are commonplace these days. It is more difficult to find time for families to shop, cook, and eat healthy meals together when both parents work. 24-hour Reports of kidnappings and sporadic violent crimes are more common in TV news. In addition to raising stress levels, this makes parents less willing to let their kids ride their bikes to the park to play.

In the end, parents drive their children to structured activities and play dates, which results in less activity for the children and more stress for the parents. Time constraints, whether from work, school, or family responsibilities, frequently cause people to eat on the run and forgo sleep, both of which can result in weight gain.

Another factor contributing to obesity may be the act of eating erratically and while rushing. According to neurological evidence, hunger and satiety signals may also be regulated by the brain’s biological clock, which is the pacemaker that governs many other daily rhythms in our bodies. These signals should ideally maintain a constant weight.

When our body fat drops below a predetermined threshold or when we require more body fat (during pregnancy, for instance), they should encourage us to eat. They should also advise us to stop eating when we are satisfied. The brain’s pacemaker and the hypothalamic appetite control center are closely linked, indicating that temporal cues influence hunger and satiety. The efficacy of these cues may be compromised by irregular eating habits, which would encourage obesity.

You are more likely to gain weight if you don’t get enough sleep. Obesity may also result from sleep deprivation, which tends to interfere with hormones that regulate appetite and hunger. The individuals who slept the fewest hours weighed the most, and those who slept less than eight hours per night had higher levels of body fat than those who slept more.

Anyone who has ever consumed too much in cookies or potato chips when feeling depressed or anxious can attest to the close relationship between stress and sleep deprivation and psychological well-being, which can also impact diet and appetite. When experiencing anxiety, depression, or other emotional disorders, some people overeat.

Consequently, being overweight or obese can worsen emotional disorders: Over time, the struggle can lead to extreme frustration, which can either cause or worsen anxiety and depression. This is especially true if you try to lose weight repeatedly and fail, or if you manage to lose weight but then gain it all back. There is a vicious cycle that results in increasing obesity and more serious emotional problems.

Genetic Causes of Obesity: Your Body’s Reaction

Your body may do the following if you are genetically predisposed to obesity:

• With fewer calories, you store more fat.
• At rest, you burn fewer calories.
• Feel hungrier or crave food.
• Feel less satisfied after eating; react poorly to conventional dieting

This explains why, even with healthy habits, some people gain weight rapidly and lose it more slowly.

The significance of genetic testing

It is not advised for all obese individuals to undergo genetic testing. It could be taken into account in situations like:

• severe obesity with an early onset.
• Genetic pattern and family history.
• obesity syndrome.
• Genetic testing may be useful in these situations for individualized diagnosis and treatment planning.

Options for treating genetically influenced obesity:

Effective treatment options are available to significantly improve health conditions despite genetic predisposition. Including

• Medical nutritional therapy is customized to meet dietary interventions and metabolic needs.
• Physical activity programs: Take into account an individual’s capacity in these planned exercise regimens.
• Pharmacotherapy: An obesity surgeon in Ahmedabad may prescribe drugs to address the patient’s hunger and metabolism.
• Weight loss surgery in Ahmedabad: In addition to restricting food intake, surgical intervention helps modify hormone signals associated with hunger and metabolism.

Genetic factors are unchangeable

• Your inherited genes: Genes linked to obesity, such as the FTO (fat mass and obesity-associated) gene, cannot be altered.
• The natural set point of your body: It may be more difficult to lose weight because of the mechanisms your body uses to maintain a specific weight, which is influenced by your genetics.
• How your body indicates when it is full: Your sensitivity to hunger and satiety hormones may be influenced by certain genes, so you may need to eat more to feel satisfied or feel less full after eating.
• Your metabolism: Your body’s ability to store fat and burn calories while at rest can be influenced by your genetic makeup.

To what extent do your genes influence your weight?

If you have most or all of the following traits, genes are most likely a major factor in your obesity:

For a large portion of your life, you have been overweight.
Your parents, one or both of them, as well as several other blood relatives, are considerably overweight. You have an 80% chance of becoming obese if both of your parents are obese.
Even if you increase your physical activity and maintain a low-calorie diet for several months, you will not be able to lose weight.

If you possess most or all of the following traits, your genetic contribution is likely to be lower:

The availability of food has a big impact on you.
You are somewhat overweight, but with a sensible diet and exercise regimen, you can reduce your weight.

You put on weight again during the holidays, after making dietary or exercise changes, or when you’re dealing with social or psychological issues.
These conditions imply that you have a genetic tendency to be overweight, but it’s not so severe that you can’t overcome it with some work.

On the other end of the spectrum, if your weight is normal and doesn’t rise despite frequent consumption of high-calorie foods and infrequent exercise, you can assume that your genetic predisposition to obesity is mild. Individuals who have only a moderate genetic predisposition to obesity have a good chance of losing weight on their own by eating fewer calories and exercising more frequently. It is more likely that these individuals will be able to sustain this reduced weight.

Is it possible to avoid obesity?

Treating obesity after it has taken hold is more difficult than preventing it. This is because your body adjusts your body mass by balancing your hunger signals with the amount of energy you expend on daily activities. Your body considers that to be your new baseline weight once it reaches a new high “set point.”

Your weight may appear higher on the scale or in the BMI table as a result of that new set point. You can avoid obesity in the future by analyzing your habits and making sensible adjustments now. Here are a few instances:

• Make minor adjustments: Do you frequently indulge in calorie-dense snacks or “pick-me-ups” like sugary drinks? Think about getting a new one. Ten extra pounds can be gained in a year with just 150 extra calories per day. That is equivalent to two double-stuffed sandwich cookies or a snack-sized bag of potato chips.
• Incorporate exercise: Consider finding an activity that suits your fitness level and burns an additional 150 calories each day.
• Make deliberate purchases: Keep healthy foods stocked in your home and reserve sweets and treats for special occasions when you go out.
• Promote general well-being by cutting back on screen time, going outside, and getting some fresh air. To maintain healthy hormone levels, control your stress, and make an effort to get enough sleep. Instead of worrying about how your efforts will impact your weight, concentrate on making positive changes and engaging in healthy activities.

How Can Genetic Obesity Be Defeated?

The idea that your destiny is predetermined by your genes is out of date. Lifestyle can “switch off” harmful genes, according to epigenetics, which studies how behavior and environment affect gene expression. Here’s how to successfully combat genetic obesity:

Incorporate a Low-Inflammation, Whole-Food Diet
Focus on lean proteins, healthy fats, and foods high in fiber.
Stay away of highly processed foods, as they may increase genetic propensities for fat storage.

Engage in Precision Exercise
Include both aerobic and strength training.
By increasing satiety and decreasing appetite, exercise can counteract the effects of the FTO gene.

Obtain Tailored Medical Assistance
For hormone evaluations and DNA-based diet plans, consult a doctor or endocrinologist.
People with severe genetic obesity may benefit from medications such as GLP-1 agonists (e.g., Wegovy).

Make sleep and stress reduction a priority
Long-term stress and sleep deprivation increase hunger hormones like ghrelin and cortisol, as well as fat storage.

Make Use of Tracking Tools and Technology
Apps that monitor activity, calories, and macronutrients can help overcome emotional eating habits or genetic impulsivity.

Conclusion

A person’s susceptibility to obesity is largely determined by their genetic makeup, which also affects metabolism, appetite, fat storage, and how the body reacts to food and exercise. Genes, however, do not determine fate.

Although you cannot alter the genetic characteristics you are born with, you can affect how those genes manifest through consistent lifestyle decisions like eating a balanced diet, exercising frequently, getting enough sleep, and managing stress. People can take practical, individualized steps toward better weight management when they are aware of both the fixed (genetic) and flexible (behavioral) causes of obesity.

FAQs

References

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• Harvard Health. (2019, June 24). Why people become overweight. https://www.health.harvard.edu/staying-healthy/why-people-become-overweight
• Is obesity maybe genetics? Explained by an obesity surgeon. (n.d.). Dr.Anand Patel. https://anandgastrosurgeon.com/can-obesity-be-genetic-explained-by-an-obesity-surgeon/
• Unraveling the genetic factors. (n.d.). https://apollodiagnostics.in/blogs/the-role-of-genetics-in-obesity-unraveling-the-genetic-factors
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• https://www.careinsurance.com/blog/health-insurance-articles/obesity-and-genetics-is-your-weight-determined-by-your-dna