The final possible issue behind stubborn weight issues may be the main stress hormone, cortisol. Too much cortisol will increase hunger levels, bringing along subsequent weight gain, especially around the midsection. The most common cause of elevated cortisol is chronic stress and lack of sleep (see tip #11), or cortisone medication (tip #10). It’s a good idea to try your best to do something about this.

Aude, Y., A. S, Agatston, F. Lopez-Jimenez, et al. “The National Cholesterol Education Program Diet vs a Diet Lower in Carbohydrates and Higher in Protein and Monounsaturated Fat: A Randomized Trial.” JAMA Internal Medicine 164, no. 19 (2004): 2141–46. doi: 10.1001/archinte.164.19.2141.

Some people feel better supplementing the already active T3 (sometimes prepared from pig thyroid glands), as it can give a stronger effect than the T4 hormone, but its effect is often harder to control. Most health professionals rarely prescribe or offer such T3 treatment, as it appears to lack significant advantages and may pose a risk when doses are high for an extended period of time. However, T3 replacement is popular among some functional medicine practitioners and naturopathic doctors. Regardless, the key is making sure you follow your levels and symptoms to make sure you aren’t over- or under-replacing thyroid hormones.
Your doctor can easily arrange for you to take a blood test to measure the concentration of thyroid stimulating hormone (TSH). If the test comes back and everything looks good, your thyroid gland is probably fine. For a more exact diagnosis, you can ask them to measure the actual levels of thyroid hormones in the blood (T3 and T4), as sometimes these are low even if the TSH is within the fairly broad normal range.
In terms of weight loss, you may be interested in trying the ketogenic diet because you’ve heard that it can make a big impact right away. And that’s true. “Ketogenic diets will cause you to lose weight within the first week,” says Mattinson. She explains that your body will first use up all of its glycogen stores (the storage form of carbohydrate). With depleted glycogen, you’ll drop water weight. While it can be motivating to see the number on the scale go down (often dramatically), do keep in mind that most of this is water loss initially.

Obviously, it’s still possible to lose weight on any diet – just eat fewer calories than you burn, right? The problem with this simplistic advice is that it ignores the elephant in the room: hunger. Most people don’t like to “just eat less”, as it may result in having to go hungry forever. Sooner or later, a normal person will likely give up and eat, hence the prevalence of “yo-yo dieting”. While it should be possible to lose weight on any diet, some appear to make it easier and some to make it much harder.