Do your genes play a role in how much you weigh? Absolutely! But before you get all excited about blaming genetics for being overweight, lifestyle factors such as diet, meal timing, and exercise are also really important.
This DIY genetics report shows you how your genetic raw data for weight-related genes are linked to your weight. We are all different, and a one-size-fits-all approach to weight loss does not work for everyone.
Let’s be honest and up-front here: Weight loss takes some hard work, and there are no magic pills based on genetics. Instead, understanding the science may help you to figure out your best path towards a healthy weight for you.
Genetics and Weight:
- Single gene mutations: There are a handful of rare genetic mutations that cause extreme obesity, beginning in early childhood. (Not included here.)
- Multiple genetic variants: For most people, the genetic component of weight is due to the combination of more common genetic variants that add together to promote weight gain, especially in an environment abundant with tasty foods.[ref]
Genetics can show us why we gain weight easily.
The variants below are organized by three icons – for appetite, circadian rhythm, and energy usage.
Many of the genetic variants related to obesity are linked to the appetite control center in the brain. Leptin (satiety signal) and ghrelin (hunger hormone) are two key hormones regulating appetite, and genes that influence their levels are linked to weight gain.
Several of the obesity-related genetic variants are important in circadian rhythm, the 24-hour built-in clock system in the body. Meal timing is important for weight management – for some people.
A couple of the genetic variants are related to the way that the body expends energy. Some people burn more calories, and some people react differently to using fat for fuel.
Genetic variants linked to weight gain:
How were these genes chosen: The variants included here are ones that have a higher impact on weight and are well researched with multiple studies backing up the claims.
Will everyone carrying the genetic variants be overweight? No. Lifestyle factors such as diet, physical activity level, and gut microbiome are all important as well. Additionally, all of your genetic variants interact, and you could also carry genetic variants related to being naturally lean.
Overview for Members:
|Gene||RS ID||Risk Allele||YOU||Notes about the Risk Allele:|
|FTO||rs9939609||A||—||Increased BMI; increased risk of obesity (variant with the largest impact)|
|MC4R||rs17782313||C||—||Increased BMI; increased risk of obesity; increased muscle mass; higher appetite|
|MC4R||rs17700633||A||—||Increased BMI; increased risk of obesity; increased muscle mass; higher appetite|
|NPY||rs16139||C||—||higher BMI, higher leptin levels, increased food intake|
|LEPR||rs1137101||G||—||Increased risk of being overweight or obese; weight gain on antipsychotic medications; greater muscle gain with weight training|
|LEPR||rs1137100||G||—||Increased risk of obesity, diabetes|
|SH2B1||rs7359397||T||—||Higher BMI, increased risk of obesity|
|CLOCK||rs1801260||G||—||Increased risk for obesity, harder to lose weight, evening chronotype|
|SLC6A14||rs2011162||G||—||Decreased fatty acid oxidation; increased risk for obesity|
|UCP1||rs1800592||C||—||Higher BMI, increased risk of obesity|
Numerous studies show that the FTO variants are linked with an average BMI that is 1.0 to 3.0 kg/m2 higher. Recent research shows that FTO is involved in regulating signaling molecules that are involved in appetite and weight regulation in the hypothalamus.[ref][ref]
- Early studies link FTO and BMI to an increased energy intake due to eating more fat.[ref]
- People with variants in the FTO gene express more FTO, possibly causing higher ghrelin (‘hunger hormone’) levels.[ref]
- Animal studies show that increased FTO causes a decreased amplitude of the core circadian rhythm genes.[ref] Disruption of the core circadian genes is linked to obesity in a lot of studies.
Check your genetic data for rs9939609 (23andMe v4, v5; AncestryDNA)
- A/A: higher risk of obesity, increased BMI, increased FTO expression[ref][ref][ref][ref] even greater impact in women with PCOS (average increase of over 20 lbs)[ref]
- A/T: increased risk of obesity, increased BMI, increased FTO expression
- T/T: typical
Members: Your genotype for rs9939609 is —.
Lifehacks for FTO:
- Time-restricted eating: The FTO gene may impact circadian rhythm. Look into time-restricted eating — essentially, eating your meals during certain hours of the day and then not eating the rest of the evening/night. Try giving your body a break from eating for more than 12 hours each night.
- Get more active: People with the highest levels of physical activity don’t seem to have an impact from the FTO gene on their BMI.[ref] Even being ‘lightly active’ is better than being sedentary for people with the FTO risk alleles.[ref]
Related article: FTO and Weight
Genetic variants that decrease MC4R levels are linked to increased BMI. MC4R is important in how the brain receives the signal from leptin, which is the satiety hormone. Without that ‘stop eating’ satiety signal, people can have an increased appetite driving them to eat a little more than what their body needs.
- MC4R deficiency is not only tied to increased appetite and higher BMI throughout life but also linked to a greater muscle mass as well.[ref][ref]
- A study looked at infants carrying the MC4R variant and found no differences in birth weight based on the variant, but, by 2 weeks of age, there is a difference in BMI and appetite.[ref]
Check your genetic data for rs17782313 (23andme v4, v5):
- C/C: risk of increased BMI in both children and adults[ref][ref][ref]
- C/T: risk of increased BMI in both children and adults
- T/T: typical
Members: Your genotype for rs17782313 is —.
Check your genetic data for rs17700633 (23andme v4, v5; AncestryDNA):
Members: Your genotype for rs17700633 is —.
Lifehacks for MC4R:
- Protein: One study found that those with an MC4R deficient variant had better weight loss results on a lower protein diet compared to a high protein diet (with no difference found for carbs and fat variation).[ref]
- Stay Active: In studies of MC4R genetic variants in childhood obesity, more active children with the variant were less likely to be obese than sedentary children with the variant.[ref]
Related article: Growing up big boned: MC4R variants
Neuropeptide Y (NPY) is released in the brain due to stress. It is abundantly found in the brain, including in the hypothalamus, where it regulates appetite. Increasing NPY in the brains of lab animals causes a many-fold increase in food consumption for the next 6 – 8 hours.[ref]
Check your genetic data for rs16139 (23andMe v4, v5; AncestryDNA):
- T/T: typical
- C/T: higher BMI, higher leptin levels, increased food intake
- C/C: (rare) higher BMI, higher leptin levels[ref][ref]
Members: Your genotype for rs16139 is —.
Lifehacks for NPY:
- Watch out for stress-eating carbs: NPY overactivation is linked to increased consumption of carbs and sweets. If you tend to stress eat, try to limit the amount of carbohydrate or sweet snacks that you have available.
- Consistency if fasting: Animal studies show that short term fasting causes an increase in NPY expression and rebound ‘hyperphagia’ (desire to eat).[ref] But longer-term fasting, or consistent intermittent fasting, may still lead to weight loss.[ref]
The LEPR gene codes for the leptin receptor. Leptin is the satiety signal that turns off your drive to eat. Most of the genetic variants below are very common; in fact, up to half of some populations carry the risk variant.
Check your genetic data for rs1137101 Q223R (23andMev 4, v5 ; AncestryDNA):
- A/A: typical
- A/G: increased risk of overweight /obesity; diabetes; PCOS;
- G/G: increased risk of overweight /obesity[ref]; diabetes[ref]; PCOS[ref]; weight gain on antipsychotic meds[ref]; greater muscle gain with weight training[ref];
Members: Your genotype for rs1137101 is —.
Check your genetic data for rs1137100 K109R (23andMe v4, v5; AncestryDNA):
- A/A: typical
- A/G: somewhat increased risk of obesity, diabetes
- G/G: increased risk of obesity, diabetes[ref][ref]
Members: Your genotype for rs1137100 is —.
Lifehacks for LEPR:
- Reduce Omega 6 Fats: People with LEPR who eat a diet low in omega-3 and high in omega-6 are at a significantly increased risk of metabolic syndrome. Adding more omega-3 fats (such as fish) and decreasing omega-6 fats (such as fried foods) may help.[ref][ref]
- Low-carb diet to reduce leptin: Cutting down on carbs (e.g. 20% or less of your calories from carbohydrates) has been shown to decrease leptin.[ref]
- Increase Melatonin: Leptin has a daily rhythm that is impacted by sleep and light. Melatonin, which is decreased by light at night, plays a key role in leptin levels.[ref][ref][ref] Increase melatonin at night by blocking out blue light or through supplementation.
- Quality Sleep: A recent study showed that people who slept 5 hours or less at night had a 15% decrease in leptin levels and a 14% increase in ghrelin.[ref]
SH2B1 codes for a signaling protein that increases the response to leptin in the brain. Without as much SH2B1, there is a decrease in leptin signaling, resulting in increased appetite and weight gain.[ref][ref]
Check your genetic data for rs7359397 (23andMe v5; AncestryDNA):
Members: Your genotype for rs7359397 is —.
Lifehacks for SH2B1:
- Watch your fat intake. Animal studies clearly show that SH2B1 is downregulated by eating a diet that is high in fat.[ref] Studies in humans show that the SH2B1 variants are linked to obesity with high dairy intake. In studies, a ‘high dairy intake’ indicates an increased amount of saturated fat in the diet (think butter and cheese instead of skim milk).[ref][ref]
The aptly named CLOCK gene codes for a key part of the core molecular circadian clock that governs your body’s rhythms over the course of 24-hours. Eating later at night is linked in numerous studies to increased weight gain.[ref][ref]
Check your genetic data for rs1801260 (23andMe v4, v5; AncestryDNA):
- G/G: higher activity in the evening, delayed sleep onset, increased risk for obesity, harder to lose weight[ref]ref][ref]
- A/G: somewhat increased risk for obesity
- A/A: typical
Members: Your genotype for rs1801260 is AA.
Lifehacks for CLOCK:
- Cut out the evening snacking: Realize that you may tend to stay up later and want to snack in the evening. Large studies show that people who eat one or two meals a day generally weigh less than people who eat 3-6 meals/day. A benefit was also shown for having a longer overnight fast.[ref]
- Mediterranean diet – meh: No beneficial effects were noted for people with the G-allele when eating a Mediterranean style diet for a year. This was in comparison to people carrying the CLOCK rs1801260 A/A genotype, who had significant benefits in insulin sensitivity with the diet.[ref]
- Get enough sleep: Not getting enough quality sleep each night is linked to weight gain. People who tend to stay up a little later may cut short their sleep each morning in order to go to work or school. Adjusting your bedtime and making quality sleep a priority may help to prevent weight gain in CLOCK variant carriers.[ref]
Related article: CLOCK: Genes at the core of our circadian rhythm
SLC6A14 (Serotonin) gene
The SLC6A14 gene codes for a transporter that regulates how tryptophan gets used for serotonin synthesis. Serotonin is a neurotransmitter important in appetite regulation and in fatty acid utilization.[ref] SLC6A14 is located on the X-chromosome, so women will have two copies of the gene and men will have one.
Check your genetic data for rs2011162 (23andMe v4 only )
- G/G: decreased fatty acid oxidation (use of fat for energy) in women, increased risk of obesity[ref]
- C/G: decreased fatty acid oxidation
- C/C: typical
Members: Your genotype for rs2011162 is —.
- 5-HTP (serotonin) is a supplement that is often advertised for fat loss. While it may work for some people, it is likely to decrease the use of fat for energy even more in SLC6A14 variant carriers.[ref]
The UCPI gene codes for Uncoupling Protein 1 found in the mitochondria of brown fat tissue. Brown fat is the ‘good’ fat that burns a lot of energy, producing more heat. People with higher levels of brown fat are more likely to be lean.
Check your genetic data for rs1800592 (23andMe v4, v5; AncestryDNA):
- T/T: typical
- C/T: slightly increased risk for obesity
- C/C: weak UCP1 activity, higher risk of abdominal fat, generally higher risk of obesity[ref][ref]
Members: Your genotype for rs1800592 is —.
Lifehacks for UCP1:
Cold exposure: One way to stimulate brown fat is by exposing yourself to the cold. Things to try include:
- Cold showers, or a shower that ends with 30 seconds of cold water.
- Turn down the heat in the winter
- Ice baths or cold water plunges (make sure you know what you are doing here!)
Caution: Being cold activates brown fat through norepinephrine release from the adrenal glands. Therefore, if you are already stressed out, have poor thyroid function, or have adrenal fatigue, using cold to induce brown fat may be adding stress to your already stressed system.
Related article: Turning up the internal heat for weight loss: UCP1
Understanding how your genes specifically relate to your weight can help you decide on a weight loss plan.
In general, sticking to an eating plan that fits with your lifestyle works best. The main premise of most diet plans is to cut out highly processed foods, avoid soda, and eliminate fast-food. Depending on your genetic data above, you may want to steer away from a lot of fat in your diet and instead include more vegetables. Others may find a higher-fat, lower-carb diet helpful for regulating appetite.
Here are a few resources to get you started:
- Time-Restricted Eating: To learn more about the science behind time-restricted eating, the book “The Circadian Code” by Dr. Panda is a great place to start.
- Paleo Diet: The ‘Paleo’ diet focuses on eating mainly vegetables, fruits, and meat – leaving out the grains and dairy. Learn more at thepaleodiet.com.
- Mediterranean Diet: Often promoted for heart health, a Mediterranean-style diet focuses on fresh vegetables, fruits, whole grains, and seafood. Learn more and find recipes on themediterraneandish.com.
- Low-Carb diet: Cutting down on carbs (e.g. 20% or less of your calories from carbohydrates) has been shown to decrease ghrelin and leptin.[ref]
Debbie Moon is the founder of Genetic Lifehacks. Fascinated by the connections between genes, diet, and health, her goal is to help you understand how to apply genetics to your diet and lifestyle decisions. Debbie has a BS in engineering and also an MSc in biological sciences from Clemson University. Debbie combines an engineering mindset with a biological systems approach to help you understand how genetic differences impact your optimal health.