THYROID TROUBLES
While most people with excess fat can lose it by fully developing an aerobic system and eliminating refined carbohydrates, some have true metabolic problems. Perhaps the most common is thyroid dysfunction. Low thyroid function is commonly associated with increased body fat. Other signs and symptoms include depression and skin problems (especially cracking around the heels and on the hands), hair loss, especially thinning of the lateral one-third of the eyebrow, and low body temperature.
If this is a potential problem, the first step is to evaluate thyroid function. Blood tests for the thyroid include free T3 and T4, and TSH levels. If these are not normal, thyroid antibodies should be evaluated. But blood tests don’t always show the relatively minor functional thyroid problems common in stubborn cases. Saliva tests may be more important for these types of evaluations. You can also take your temperature—those with low thyroid function usually have low temperatures. Below-normal temperatures—less than about 98.6˚F (37˚C)—may indicate thyroid dysfunction. (Note that NSAIDs can also disturb metabolism and decrease body temperature.)
If you make the necessary corrections, whether it’s improving your diet, building the aerobic system, or others (including the right combinations), your thyroid function should improve and fat burning should increase. This will be reflected in a more normal body temperature and any other blood or saliva tests. In some cases, you may have to find a health-care professional who can help you improve thyroid function.

There are varying ways to measure body size, and even percentage of body fat. And many weight-loss programs sell various gadgets for determining the amount. But in keeping with simplifying the stress in your life, my suggestion is to avoid the task of trying to focus on these more detailed measurements—and avoid the risk of creating a new obsession of weighing yourself. Reducing body fat should be done in a healthy way. Start with the Two-Week Test (see chapter 14).