All of these allergies and sensitivities can cause inflammation and disrupted digestion and ultimately leaky gut/dysbiosis, which can further interfere with weight-loss efforts. As a thyroid patient, you are also at greater risk of candidiasis - yeast overgrowth - and the sensitivity or allergy to yeast can become an impediment to effective weight loss. Thyroid disease seems to make people more likely to have food allergies and sensitivities (e.g., wheat, milk, cheese, eggs, soy, and citrus allergies). One of the known causes of thyroid problems is celiac disease, or gluten intolerance and sensitivity. Thyroid patients may have difficulty getting restorative sleep, which affects fat burning, serotonin, and hormone levels. It can also make you less likely to exercise and disrupt your ability to get restorative sleep. Depression is known to trigger eating in some people and especially increase carbohydrate cravings. Thyroid disease can trigger or worsen depression.

This increased craving for and intake of carbohydrates appears to stem from various changes in brain chemistry and sympathetic nervous system activity due to the thyroid condition. Dutch researchers studying the energy and nutrient intake of thyroid patients found that thyroid disease and hyperthyroidism in particular may be linked to increased appetite for carbohydrates. When you are tired, one of the body's ways to try to generate energy is to increase your appetite, encouraging you to eat to get energy. Many people with thyroid problems experience ongoing fatigue. And reduced muscle mass also reduces metabolism.

In both cases, the less you exercise and the less physical activity you have, the more likely you are to lose muscle mass. Thyroid disease also commonly causes joint and muscle aches and pains, carpal tunnel syndrome, tarsal tunnel syndrome, and tendonitis, all of which make exercise and movement harder and may discourage you from exercising. This level of fatigue may mean that you exercise less and move around less, which reduces the amount of energy you expend. When you have a thyroid dysfunction, even with optimal treatment you may feel more fatigued than normal. This sort of diet wreaks havoc on the metabolism, making it think that you are facing starvation and turning on a whole host of appetite-increasing, fat-storing hormones, slowing the metabolism in order to prevent possible starvation. Many thyroid patients have already gone to extremely low-calorie starvation diets in attempts to lose weight. This reduced oxygen utilization makes cells less effective at converting food into energy - another factor that encourages fat storage.