UCP1 diverts energy from being stored as fat and instead helps turn it into body heat. Could this gene affect weight gain and obesity? Read on to learn all about UCP1 and its effects on energy and metabolism.
What Does UCP1 Do?
There are three main types of fat (adipose) tissue:
- White fat: this is what many people think of as “body fat.” This is the body’s primary form of energy storage; people with too much white fat are considered obese [R]
- Brown fat: also called “good fat”. Brown fat is burned to generate heat and maintain body temperature [R]
- Beige fat: when white fat starts working like brown fat and burns calories, it is called beige fat. White fat is converted into beige fat in a process called “browning” [R, R]
UCP1 (uncoupling protein 1) is mainly found in the mitochondria of brown and beige fat cells. It’s also called thermogenin because it helps generate heat by a process called non-shivering thermogenesis, which helps our bodies stay warm in cold environments [R, R, R, R, R].
Because it prevents excess energy from being stored as body fat (and instead turns it into heat), many researchers believe that UCP1 could protect against weight gain and obesity [R, R, R].
In this post, we’ll look into the UCP1 gene, which may be associated with weight gain and obesity [R, R].
Before we proceed, however, it’s important to note that there are many different genes that affect your metabolism and likelihood of being overweight — and UCP1 is only one of them! We will address more weight-associated genes in our upcoming posts.
If you believe that your genes are making it more difficult to lose weight, talk to your doctor about the information and strategies in this post.
The UCP1 protein diverts energy from being stored as fat and instead helps turn it into heat. Because of this, some researchers believe that UCP1 activity protects against weight gain and obesity.
Your UCP1 Genotype
One of the best-studied SNPs in the UCP1 gene is rs1800592 (also known as the “-3826 A>G” polymorphism). It helps determine how your body uses and stores the energy that you get from food [R].
There are two possible variants (alleles): ‘T’ and ‘C’.
The ‘T’ allele is linked to increased activity of the UCP1 gene. It’s associated with a higher resting metabolic rate, higher body heat production, and less weight gain. According to some researchers, this variant helps turn more of the energy from food into heat instead of body fat (white fat) [R, R].
Conversely, the ‘C’ allele is linked to decreased activity of the UCP1 gene. It’s associated with a lower resting metabolic rate, lower body heat production, higher weight gain, and a higher BMI. If less of the energy acquired from food is turned into heat, then more of it would get stored as body fat [R, R].
You can see your genotype for this SNP in the table below:
SNP Table
variant |
genotype |
frequency |
risk allele |
rs1800592
|
|
|
|
(Note that alleles are given in the “plus” orientation to match with your raw data. Scientific studies may report it in the “minus orientation” — so if you click through to our sources, you may see ‘A’ and ‘G’ alleles rather than ‘T’ and ‘C’ alleles, but this isn’t a mistake! To convert between the two, ‘C’ = ‘G’ and ‘T’ = ‘A’.)
The ‘T’ allele is associated with increased metabolic rate and higher body heat production. The ‘C’ allele, by contrast, is associated with decreased metabolic rate and increased weight gain, body fat content, and BMI.
UCP1, Metabolism, and Body Weight
According to several studies, the ‘C’ allele (and especially the ‘CC’ genotype) is associated with increased weight gain as well as a higher chance of being obese [R, R, R, R, R, R, R, R].
For example, people with the ‘CC’ genotype were found to have lower basal metabolic rates than people with the ‘T’ allele. In other words, they burned less energy when resting. In fact, one study reported that ‘C’ carriers may burn as much as 200 fewer calories per day than people with the ‘TT’ genotype [R, R]!
Apart from burning less energy when resting, people with the ‘CC’ genotype also produced less heat when exposed to cold [R, R].
We all lose brown fat as we age. However, in one study, people with the ‘CC’ genotype had less brown fat at a younger age than people with the ‘T’ allele [R].
Finally, several studies link the ‘C’ allele and the ‘CC’ genotype to metabolic disturbances commonly associated with being overweight. In various studies, the ‘C’ allele has been associated with elevated blood pressure, greater insulin resistance, and higher LDL cholesterol and triglycerides [R, R, R, R, R, R].
Despite this strong body of evidence, additional research is required to determine whether the ‘C’ allele is the direct cause of these problems.
Researchers have found a potential link between the ‘C’ allele at rs1800592 and slower resting metabolism, weight gain, and obesity. According to some studies, the ‘C’ allele is also associated with high cholesterol and insulin resistance.
The UCP1 'T' Allele: An Adaptation To Cold?
Fun fact: worldwide, about 30% of people have the ‘TT’ genotype, which is associated with higher resting metabolism and increased heat production. But this genotype is much more frequent in Europe, where 58% of people have it! Many researchers believe that the UCP1 gene and the rs1800592 SNP are in part responsible for human adaptation to colder climates [R].
Sure enough, a study of 52 populations worldwide found that the ‘T’ allele was considerably more common in colder regions [R].
However, although today we consider the ‘T’ allele beneficial in terms of its potential effect on body weight, this allele is essentially linked to lower metabolic efficiency. In other words, people with this allele may “waste” more of the energy that they get from food on generating body heat [R].
Some researchers have suggested that the more efficient ‘C’ allele may be advantageous when food is scarce and the climate is warm [R].
The ‘T’ allele is more common in colder climates, where increased body heat production is advantageous.
Recommendations
Diet and Exercise
The best-studied and most effective means of losing weight are exercise and a healthy diet. There’s some disagreement about exactly which diets are best; however, eating less food overall as well as reducing your intake of refined sugars (like in soda, sweets, and baked desserts) is a very good place to start [R, R].
People with the “C” allele burn less energy and may thus want to control their daily calorie intake to avoid weight gain issues.
Researchers don’t fully understand the effect of exercise on UCP1 specifically. Early animal studies suggest that it may induce fat browning, implicating UCP1 in the transformation. This may be one reason why physical activity has long been recognized as vital to any weight loss program [R, R].
According to some studies, increasing caloric and carbohydrate intake may increase UCP1 activity. However, carbs and overeating have also been associated with weight gain and other detrimental effects, so they are not recommended for the purpose of increasing UCP1 [R, R, R, R].
Cold Exposure
Perhaps the easiest strategy associated with increased UCP1 activity is exposure to cold, for example by doing cryotherapy, taking a cold shower, or engaging in outdoor activities during the winter months [R, R, R].
According to some studies, cold exposure increases your fight-or-flight (sympathetic) response and promotes the release of norepinephrine, which then activates UCP1 [R, R].
Indeed, studies have found that UCP1 and brown fat in general are more active in winter when temperatures are low [R].
However, because it activates the fight-or-flight response, cold exposure may not be good for everyone. Consult your doctor to find out if cold exposure is right for you and make sure you are not over-stressing your body.
Supplements
Iron deficiency may impair UCP1 activity, leading to decreased brown fat and increased white body fat [R].
Iron-rich foods like beef and liver are the best dietary sources. Iron can be dangerous in excess, so it’s important to only take supplements if your doctor recommends them [R].
The following foods and supplements may be of interest to people who are ‘C’ carriers:
- Fucoxanthin: this carotenoid is found in edible brown seaweed, such as kelp/kombu or wakame. In one study, people with the ‘CC’ genotype who took fucoxanthin had decreased blood sugar [R].
- Doenjang: Korean fermented soy paste. Supplementing with doenjang was associated with reduced body fat in ‘C’ allele carriers [R].
According to one study, people with the ‘TT’ genotype lost more weight when they supplemented with ginger [R].
The following foods and supplements have been associated with increased UCP1 and brown/beige fat in animal studies, although it’s not yet certain if they are as effective in humans. It’s especially important to talk to your doctor before trying supplements that haven’t had sufficient human research.
- Green and black tea [R, R]
- Caffeine [R]
- Cocoa and chocolate [R, R]
- Olive oil [R]
- Mulberry [R, R, R]
- Rutin (found in apples, buckwheat, citrus fruits, figs, and tea) [R]
- Quercetin (abundant in red onions and kale) [R, R]
- Resveratrol (found in red grapes, berries, and peanuts) [R, R]
- Isoflavones in soy and soy products [R, R]
- Fish oil / omega-3 fatty acids [R]
- Allulose [R]
- Berberine [R]
- Luteolin (found in carrots, peppers, celery, olive oil, peppermint, thyme, rosemary, and oregano) [R]
- Myricetin (grapes, berries, and other fruits and vegetables) [R]
- Hesperidin (citrus fruits) [R]
- Chrysin (propolis, honeycombs, and mushrooms) [R, R]
Biljana received her PhD in Ecological Genetics from Hokkaido University.
Before joining SelfHacked, she was a research scientist with extensive field and laboratory experience. She spent 4 years reviewing the scientific literature on supplements, lab tests and other areas of health sciences. She is passionate about releasing the most accurate science & health information available on topics, and she's meticulous when writing and reviewing articles to make sure the science is sound. She believes that SelfHacked has the best science that is also layperson-friendly on the web.
Disclaimer
The information on this website has not been evaluated by the Food & Drug Administration or any other
official medical body. This information is presented for educational purposes only, and may not be used
to diagnose or treat any illness or disease.
Also keep in mind that the “Risk Score” presented in this post is based only on a select number of
SNPs, and therefore only represents a small portion of your total risk as an individual. Furthermore,
these analyses are based primarily on associational studies, which do not necessarily imply causation.
Finally, many other (non-genetic) factors can also play a significant role in the development of a
disease or health condition — therefore, carrying any of the risk-associated genotypes discussed in this
post does not necessarily mean you are at increased risk of developing a major health condition.
Always consult your doctor before acting on any information or recommendations discussed in this post —
especially if you are pregnant, nursing, taking medication, or have been officially diagnosed with a
medical condition.
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