The Key to Successful Weight Loss is in Our Receptors
Fat Receptors Can Help or Hurt Weight Loss Efforts
For some of us, losing weight seems like an impossible feat. No matter how hard we try, the fat will not budge!
Could the reason be due to those things on our fat cells called receptors?
Let us find out!
Fat cells are essential for weight loss (and gain). They have “doors” that determine how much fat is held and/or released from the cell. But there are things on our fat cells’ “doors” that can control how much goes in and out. Those things are called receptors, and their activity (or inactivity) is critical. As experts put it, fat cell receptors are the “locks” that determine if the “door” opens.
Some may ask: Okay, how do we open the “lock” that eventually opens the “door” so I can FINALLY lose this stubborn fat?
Well, just like with our homes, we need a key. Hormones and other compounds are the “keys” that bind to the fat cell receptors, initiating their activity (or inactivity).
To summarize, fat cells have doors, the receptors are the locks, and hormones (and other compounds) are the keys. They all work together to determine how much fat the fat cells keep and/or release.
In this article, we will look at the fat cell receptors that can either hinder or help weight loss. We will also look at different ways to get these receptors to work for us!
What are adrenergic receptors?
Adrenergic receptors perform many bodily functions. It would take forever to try to discuss them all here. In a nutshell, adrenergic receptors are comprised of two different types: alpha and beta. Both receptors are present in nearly every cell.
Fat cells also have adrenergic receptors (1).
This article will focus on the adrenergic alpha-2 and beta receptors in the fat cells.
Alpha-2 receptors are three to four times more abundant than beta receptors in fat cells. They are also abundant in areas where the fat is the last to go; the “stubborn” fat (2).
These areas typically include the hips and thighs for women and the belly and back areas for men.
Women who are “apple-shaped” tend to store most of their fat in their belly area or upper body. Thus, they would have more alpha-2 receptors located around their stomach area or upper body.
Beta receptors are abundant in places where we typically lose weight fast. They make it easier to lose weight in those areas because they are more responsive to hormones and substances that regulate fat burning.
For the rest of this article, we will refer to alpha-2 receptors as a2-receptors and beta receptors as b-receptors.
How to Get A2-receptors and B-receptors to Help Us Burn Fat
A2-receptors either keep fat in the fat cells or release it very slowly; however, b-receptors release fat faster.
One of the main weight loss goals is to block the a2-receptors and activate the b-receptors in the fat cells.
Key takeaway: A2-receptors reserve fat; b-receptors release fat.
How to Turn the A2-Receptor from Foe to Friend
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- Do not constantly release insulin.
- Consider intermittent fasting as it reduces a2-receptor activity (3).
- Follow a low-carb diet because it tends to lower insulin secretion which would reduce a2-receptor activity.
How do we keep b-receptors in a constant state of releasing fat from the fat cells?
A2-receptors are antilipolytic.
On the other hand, b-receptors are lipolytic.
Lipolytic (i.e., lipolysis) action mobilizes fat from the fat cells so the body can use it as an energy source.
A report published in the American Journal of Clinical Nutrition stated that b-receptors are sensitive to various hormones like insulin, androgens (e.g., testosterone), nutritional status (e.g., healthy or unhealthy diets), and exercise (4).
How to Manipulate These Receptors into Helping Us Burn Fat
Weight loss is achievable by manipulating these receptors. Even if some of our fat cells have more a2-receptors than b-receptors, we can still trigger the b-receptors to release fat.
Both natural and synthetic methods can either activate b-receptors or block a2-receptors.
Catecholamines are natural compounds (e.g., epinephrine and norepinephrine) that act on adrenergic receptors (5).
Epinephrine and norepinephrine increase fat loss by regulating alpha and beta receptors in the fat cells (5).
The problem with catecholamines is that they bind to both a2 and b-receptors (5). However, by blunting a2 activity, they can attach to the b-receptors and promote fat loss.
Synthetic Methods of Regulating A2-Receptors and B-Receptors for Fat Burning
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Yohimbine
Yohimbine extract may help shed fat due to its ability to block a2-receptor activity and promote lipolysis. It may also encourage fat loss by improving blood flow to the fat cells, thus helping increase fat burning (6).
In a study with overweight participants who used yohimbine, researchers concluded: “The results obtained warrant further research on the applicability of alpha 2-receptor inhibitory drugs as a supplementary management in the treatment of obesity.” (6a)
Caution is needed with the dosage of this extract, as it may have dangerous effects on one’s heart and blood vessels, resulting in several side effects. In weight loss supplements, it usually goes under Yohimbine HCI or HCL.
Standardized P-Synephrine
This alkaloid is obtained from bitter oranges and may help lower body fat by temporarily increasing caloric burn. It also blocks the a2-receptors while stimulating the b-receptors (7).
Caffeine
It is the most consumed stimulant worldwide. Tea, coffee, and chocolate contain different amounts of caffeine, with coffee having the highest concentration. It is also available as a standalone supplement. In the short-term, caffeine helps the body burn more calories but, it also temporarily blocks a natural substance called adenosine.
Adenosine helps relax and dilate blood vessels but blocks or limits the release of catecholamines. Because adenosine is blocked, it allows catecholamines to promote the release of fat from the fat cells (8).
Green Tea
The EGCG in green tea stops the breakdown of norepinephrine (a catecholamine) which helps release fat from the fat cells so the body can use it for energy. Some studies show that EGCG may help the body burn more calories throughout the day (9).
Natural Ways to Control A2 and B-Receptors for Fat Loss
Many people either do not or cannot use supplements and prefer to regulate a2 and b-receptors naturally. Additionally, some may wish to combine both natural and synthetic methods.
Here are some natural ways to help manipulate these receptors:
Intermittent Fasting
The basic concept of intermittent fasting means consuming food at certain times combined with a stretched-out period of not eating (fasting). The recommended fasting time is 12 to 18 hours after your last meal of the day.
For example, if your last meal is 7:00 pm, then you do not consume food (including snacks)/sugary beverages until at least 7:00 am the next day. Some may choose to extend their fasting past the 12-hr minimum.
According to experts, including research from the University of New Mexico, insulin is secreted after consuming food (e.g., high-carb foods). When this happens, it keeps fat inside the fat cells.
Intermittent fasting can lower insulin, reduce a2-receptor activity, and enhance b-receptor stimulation. It also increases catecholamines, allowing more fat mobilization from the cells so the body can use the fat as energy (10).
Low Carb Diets
While I do not advocate for any diet, low-carb diets reduce insulin secretion. Lowering insulin secretion reduces or inhibits a2-receptor activity in fat cells (11).
Improve Blood Flow
Good blood flow is essential for circulating blood, oxygen, nutrients, and other substances to all parts of the body. A body with better blood flow can mobilize fat from fat cells and use it as an energy source (12).
Poor blood circulation could make it easier for fatty acids to re-enter the fat cells (12)! Some ways to improve blood flow and circulation include dry brushing, reducing stress, consuming foods that increase blood circulation, massages, staying away from cigarettes, warm baths, using compression gear, and taking periodic “stand-up breaks.” Sitting down for too long can reduce blood flow.
Check out: Sitting Too Much Leads to Weight Gain, Poor Blood Circulation, and More
Exercise
Exercise improves blood flow to fat cells, including the stubborn fat areas. In addition, the fat released from fat cells becomes an energy source for the muscles during exercise, reducing their re-circulation (13).
According to experts, including researchers from the University of New Mexico, exercise regulates insulin levels. It also increases catecholamines (e.g., norepinephrine), thus inducing lipolysis and fat loss (13).
Research continues to show the many health benefits of exercise, including “reduction of adipose tissue mass“ (i.e., fat mass) and improved metabolism (13a).
Check out: Exercise Boosts Brain Power, Lowers Cancer Risk, and Much More!
Address Physiological Issues
The previously mentioned suggestions are some ways to help burn fat. However, other factors can, both directly and indirectly, stimulate the a2-receptors to store fat and block the b-receptors from releasing fat.
If it were as simple as intermittent fasting and cutting carbs, everybody would be at their goal weight. And, more importantly, be able to maintain it.
I recommend working with a doctor, dietitian/nutritionist, integrative medicine practitioner, or health coach to help address physiological issues making it difficult to achieve permanent weight loss.
It’s important to address these physiological issues because they have a domino effect on alpha and beta receptors.
In my e-book, I address physiological issues that can directly or indirectly affect the receptors we read about in this article. For example, I discuss a condition that while primarily affecting women, men can get too. This condition promotes weight gain and could stimulate a2-receptor activity.
Final Thoughts
Anyone on a weight loss journey should understand how receptors work and the role they play in the process of losing weight.
When we thoroughly understand the physiological obstacles that stand between us and the achievement of our goals, we are more equipped to successfully lose weight.
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