Weight loss is often explained in terms of calories: if you consume more calories than you burn, you gain weight. Reverse the formula for more calories burned than consumed, and you’ll lose weight. In truth, however, our bodies are more complex than that, and weight loss isn’t such a simple formula. Why? There are many contributing factors, including calorie inaccuracies, non-exercise activity thermogenesis (NEAT), and perhaps most importantly, hormones. Specifically, metabolic hormones like leptin, ghrelin, and insulin.
Let’s take a look at the most important metabolic hormones and how they affect appetite, fat storage, metabolism, and more.
Metabolic Hormone #1: Insulin
Produced in the pancreas, insulin is secreted throughout the day in small amounts, with increased amounts after meals. It allows the cells to take in nutrients as well as blood sugar for either energy or storage, and it’s also the body’s primary fat-storage hormone. That is, it lets the body know if it needs to store fat or prevent fat from being broken down.
Unfortunately, insulin levels are often elevated due to overeating, especially when too much sugar, refined carbs, or highly processed foods are consumed, which can lead to insulin resistance. Insulin resistance is a common condition in which blood sugar levels are raised but the body responds with even higher than expected levels of insulin.
This condition leads to a host of negative consequences, including weight gain, obesity, belly fat, and metabolic syndrome. As a result, both insulin resistance and rates of obesity have sharply risen over the last 30 years with over 32.2% of the U.S. population estimated to have the condition.
To help normalize insulin levels and overcome insulin resistance:
- Exercise, such as a brisk walk, daily.
- Eat a diet that’s made up of whole, unprocessed foods, and consume more protein.
- Lose belly fat.
- Quit smoking if you currently smoke.
- Get plenty of quality sleep every night.
- Reduce stress levels by meditating.
- Decrease sugar consumption, especially in the form of added and liquid sugar like soda.
- Get plenty of healthy omega-3 fats as found in fatty fish, walnuts, flaxseeds, and chia seeds.
- Reduce carbohydrate consumption, especially simple carbohydrates, which are lower in fiber.
- Decrease oxidative stress and inflammation in the body.
- Try intermittent fasting.
- Ensure you are getting enough magnesium, which is found in avocados, nuts and seeds, legumes, whole grains, leafy greens, or as a supplement.
- Consume green tea or a green tea extract.
Metabolic Hormone #2: Leptin
Your fat cells produce leptin, which is known as the “satiety hormone” as it’s supposed to let you know when you’re full and have enough fat stored and thus prevent overeating. It has other functions in the body that relate to cognition, immunity, and bone metabolism. Yet its key role is to communicate with the brain (i.e., the hypothalamus) to regulate food intake. When leptin levels lower, hunger and appetite are increased, and the desire to exercise and burn calories is decreased.
Surprisingly, however, many people who are overweight or obese have high levels of leptin coursing through their veins (up to 4 times more than those folks at a normal weight). So, they should be experiencing decreased appetite, so they’ll eat less and lose weight.
Yet just as some people experience insulin resistance, many people have leptin resistance where the signaling is impaired. Even with plenty of fat stored, if the system isn’t working properly, the body may think it’s starving, driving people to continue to eat. In fact, leptin resistance is now thought to be a leading driver in increased weight (i.e., fat) gain.
To help normalize leptin levels and increase leptin sensitivity:
- Exercise regularly, especially moderate aerobic exercise.
- Get plenty of quality sleep (between 7 and 9 hours per night).
- Avoid inflammatory foods like those that are highly processed, fried, or high in trans fats and added sugars or refined carbohydrates.
- Eat more anti-inflammatory foods like fatty fish, cherries, berries, broccoli, avocados, peppers, mushrooms, tomatoes, green tea, and spices like turmeric.
- Lower triglyceride levels.
- Ensure you’re eating enough protein.
- Support a healthy gut microbiota.
- Consider supplementation with ingredients shown to help improve leptin functioning, such as those found in Tetrogen™.
Metabolic Hormone #3: Ghrelin
While leptin is the “satiety hormone,” ghrelin is the “hunger hormone,” which is produced in the gut. When your stomach is empty and starts to growl, the body sends the messenger (i.e., ghrelin) to the hypothalamus to give it the signal to eat. The higher your levels of ghrelin, the hungrier you feel. This explains why ghrelin levels tend to be high before eating and low about an hour after you’ve eaten. Its purpose is to stimulate appetite, so you’ll consume more food and store fat to prevent starvation.
Ghrelin also affects other functions in the body like the sleep/wake rhythm, learning and memory, reward-seeking behavior, carbohydrate metabolism, and taste sensation.
Unfortunately, in people who are overweight or obese, ghrelin doesn’t seem to do the job as well as its should. Research, for example, has found that fasting ghrelin levels are lower in overweight people than in normal-weight people. In addition, after a meal, obese people tend to see only a slight decrease in ghrelin. And other research indicates obese folks may have overactive ghrelin receptors, which can lead to consuming more calories. And dieting itself can increase levels of ghrelin by 24% to 40% to try to protect the body from starving, especially when weight is lost.
To help normalize the function of ghrelin:
- Consume protein with every meal, especially breakfast.
- Reduce your intake of sugar, especially liquid sugar drinks like soda.
- Avoid being overweight or underweight, maintain a stable weight, and avoid binge-eating and yo-yo dieting.
- Ensure you get plenty of quality sleep.
- Increase your muscle mass.
- Implement calorie cycling such as intermittent fasting.
Other Key Metabolic Hormones
Other metabolic hormones, like cortisol, estrogen, neuropeptide Y, glucagon-like peptide-1, cholecystokinin, and peptide YY, all play various roles in helping individuals lose or maintain weight.
To help support these hormones and improve your results, in addition to the suggestions above:
- Consume a balanced, whole-food-based diet that’s high in vegetables.
- Control calories, but don’t cut them too low, and ensure you’re eating enough protein.
- Start meditating regularly.
- Enjoy listening to music to help reduce stress.
- Get plenty of quality sleep.
- Eat fiber-rich foods, including cruciferous vegetables, leafy greens, and flaxseeds.
- Avoid fasting for longer than 24 hours.
- Consider supplementing with a quality probiotic or consuming probiotic foods like yogurt or kefir.
Calories do count, but losing weight is more complex and nuanced than just calories in versus calories out. Fortunately, simple lifestyle changes like staying active and exercising regularly and ensuring you are eating plenty of protein and fiber can help increase your ability to balance hormones for both sustained weight loss and improved health.