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1. Metabolism moving at a crawl
Thyroid hormones keep everything humming along. The masters of energy conversion, thyroid hormones (TSH, T3, and T4) drive virtually every cell in your body. When all three hormones are functioning as a team, your metabolism is a fat-burning machine. Stress, allergic responses, or just getting older can throw them off.
Growth hormone (GH) and acetylcholine are also essential to the metabolism equation. They're released when you sleep and work to repair and build muscle tissue. Over-exercising and skimping on sleep can get in the way of burning fat and keeping your metabolism revved. Stress increases belly-broadening cortisol and suppresses your GH levels.
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2. Insulin insensitivity
Adiponectin is essential to the fat-burning process. A hormone that is produced in our fat cells, adiponectin helps us lose weight by increasing our insulin sensitivity. Remember, insulin tells us whether to store or burn fat. So if your body is more in tune with your energy needs, you'll lose the pudge—and not muscle tone—more easily. Greater levels of adiponectin mean more energy burned, even at rest. Eating a high-carb diet and skipping exercise will knock this hormone out of whack.
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3. Low energy
When we eat carbs, insulin spikes, telling our bodies to store fat—too many carbs, too much fat. But we can't cut out all carbs forever—we need some for immediate fuel, otherwise we create a bad hormonal chain reaction that can affect our energy levels. Plus, you want to be burning sugar (not protein) for fuel to maintain muscle tone.
This is where the hormone glucagon plays a role—it helps regulate blood sugar levels, telling the body when to use stored fat and sugars, say, after you exercise. If you're not getting enough fruits, veggies, or whole grains, along with protein, you may have low glucagon levels, and throughout the day feel like you're swimming through pudding.
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4. No gas when you need it
Another hormone, adrenaline, accelerates fat loss and boosts energy. Also known as epinephrine, adrenaline is responsible for quickly revving you up (think fight or flight response and how that makes you feel).
This handy hormone allows the body to free up stored fats and sugars so you have that burst of energy when you really need it. If you're too frequently in an amped up state, though, you're overproducing adrenaline, which means that when you really have to step on the gas, the tank will be empty.
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5. MIA libido
A key sex hormone, DHEA, is also often touted as the anti-aging hormone. While it boosts libido and helps you feel focused, youthful, and energetic, it amps up your immune system, too. DHEA, along with testosterone, protects muscle tissue, which burns more calories than fat. DHEA and testosterone naturally decline with age, stress, and illness. Many times when your libido is low, you're not sleeping well either, and as studies show, poor sleep translates to weight gain.
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Boost your fat-burning hormones by exercising (walking or strength training at least 5 days a week), getting at least 7½ to 9 hours of sleep, and eating nutritionally balanced meals (that means trying to eat one protein, one carb, one fat, and one fiber at each meal, four times a day).
To balance your thyroid and growth hormone, in addition to sleep and exercise, make sure you consume lean protein based on your body weight and gender—most women need about 38 grams a day.
If your adiponectin and/or glucagon levels are low, eat a low-carb diet, including healthy fats, to support your insulin balance and keep your blood sugar in check, in addition to walking and weight training.
When it comes to boosting your DHEA, meditate to boost serotonin for better sleep. (Sleep also regenerates the adrenal glands, which produce DHEA and reduces cortisol.) Also, have sex at least twice a week—orgasms spark DHEA levels, too! Any stress-reducing activity will stimulate this essential hormone.