Obesity is a complex and chronic disease that has been representing a major issue for the US. With nearly 1 in 3 adults being overweight, 2 in every 5 adults being obese, and 1 in 5 children being obese, it is obvious that obesity has become an epidemic. And while many try to convince you that “health looks different for everyone,” it is clear from science and numerous studies that obesity is dangerous and that it is a risk to a load of other chronic illnesses such as diabetes, hypertension, cardiovascular diseases, and others. So as my colleagues in the Mayo clinic have correctly stated:
“Obesity is not a cosmetic issue.”
For that, scientists have been looking for more effective ways to help prevent and reverse obesity. And one that has been of interest lately is activation of brown adipose tissues, which is what we will explore in this article.
Why Do We Need More Approaches to Weight Loss?
Many of you might be wondering, Why are we even looking into this? We have exercises, and we have diets. I will tell you why.
1. Diet and Exercises
Dieting and exercising are very effective, and they are the most common methods by which people lose weight in the long term. Diets (such as keto, paleo, clean eating, and Mediterranean diets) and exercises need to be maintained, and there is always a risk of regressing and gaining back most of the lost weight.
2. Bariatric Surgery
Bariatric surgery is also an effective way to lose weight and maintain weight loss for a long time. However, it comes with a high morbidity and mortality risk. Beside long term side effects such as pernicious anemia.
3. Drugs
Over the years, many pharmaceutical drugs have been approved for the treatment of obesity and then withdrawn later on for their side effects and risks. Such as sibutramine, which increases the risk for heart attack and stroke. Ozempic, a drug that has been very famous lately after many celebrities used it for weight loss, has become quite popular, but now some studies about its relationship to some risks are surfacing.
So, as you see, with the limitations that accompany the available treatments, scientists are still looking for effective treatments for obesity.
Brown Fats
Brown fats, or brown adipose tissues, are a type of tissue responsible for regulating your body temperature. Some of you who have heard of it probably connect it with babies. That is because for a long time, brown adipose tissues were believed to be in infants; they were known for regulating body temperature in infants. But now we know that even adults have brown adipose tissue, albeit to a lesser amount.
The difference between white fats and brown fats is that white fats, which represent the majority, are where energy is stored, and too much of it is the cause of obesity. Brown fats, on the other hand, are smaller; they store energy and burn that energy for thermogenesis. A third type of fat is beige fats, which are a combination of white and brown adipose tissues. They burn calories by converting white cells to brown fat cells.
Brown Fat Activation and Obesity
What studies came to find is that brown fat activation can help with weight loss.
How to Activate Brown Fats
Increasing the amount of brown fats in the body, or in other words, activating brown fats, can lead to energy expenditure and weight loss. There are some methods that you can use to activate the brown fats in your body. Some of them are more effective than others, and some hold more risk. Here is how you can activate brown fat.
1. Exposure to Low Temperature
Since a major function of brown adipose tissues is to emit heat and warm up your body by non-shivering thermogenesis, it only makes sense that exposure to low temperatures would lead to activation of brown adipose tissues. This is considered being the most classic way to activate brown adipose tissues.
Exposure to low heat induces the sympathetic nervous system to produce norepinephrine, which regulates brown fat cells. However, activation of the sympathetic nervous system for a long time can carry serious cardiovascular risk, especially for those who are already prone to them. That is because norepinephrine increases heart rate and blood pressure, and for longer durations, that can be dangerous.
In a nutshell, exposure to mild cold can be used as a treatment against obesity, all while bearing in mind the risk for people with cardiovascular diseases.
2. Exercises
In 2012, a group of scientists (Boström et al.) identified a new compound (irisin) that gets released into the circulation during exercise and triggers the transformation of white adipose tissue to brown adipose tissue in mice. But irisin is not the only compound that gets released during exercise and leads to activation of brown fats. You might all be familiar with the catecholamines that are secreted during exercise, and they too contribute to the browning of white adipose tissue.
4. Dietary Pattern
Special dietary patterns can induce the browning of white adipose cells in addition to increasing the thermogenesis of brown fat cells. These patterns include one-day feeding, one-day fasting, and intermittent fasting (one-day fasting, two days eating). The advantages of dietary patterns over low heat exposure are that they do not involve stimulation of the sympathetic nervous system, and hence there is no cardiovascular risk, providing by that a better approach for obesity treatment.
5. Nutrients
Some of the small molecules in vegetables and fruits have the potential to activate brown adipose tissue, browning white fat cells, and prevent and treat obesity. For example, long-term consumption of the compounds below can induce energy consumption and promote weight loss.
Capsaicin in hot pepper
Green tea
Parviflora extract
Thymol in thyme
Chrysin in flowers mushroom
Curcumin in turmeric
Resveratrol in red cabbage and berries
Tea catechins in cocoa Oolong pu erh
EPA and DHA in fish oil
Paradol in ginger
Quercetin in broccoli, berries, and asparagus
Caffeine in coffee
Carotenoid in edible seaweed
Allicin in garlic and onion
Ginsenosides in panax Ginseng
Rubi fructus extract
Menthol in mint
Rutin in mulberry
6. Brown Fat Transplantation
Since the discovery of brown fats in human adults, the focus of many studies has been to increase the amount of brown fats in the body. Most, if not all, the studies were conducted in mice. When we transplant brown fat cells, those cells lose their thermogenic function, but they induce the thermogenesis of endogenous brown fat cells. In diabetic rats, brown adipose tissue transplantation reversed the symptoms of diabetes. The results of those studies so far show that brown fat cell transplantation might reduce obesity. However, there is a question of how those results will translate into clinical trials.
Takeaway
The increased rate of obesity and the dangerous complications related to it call for further treatments. Brown adipose tissue activation through different mechanisms provides a promising treatment for reversing and controlling obesity. However, more research is needed.
References and Citations
Liu, X., Zhang, Z., Song, Y., Xie, H., & Dong, M. (2023). An update on brown adipose tissue and obesity intervention: Function, regulation and therapeutic implications. Frontiers in endocrinology, 13, 1065263. https://doi.org/10.3389/fendo.2022.1065263
Comments