In this discussion we take a look at the effects of taking thyroid hormones and excessive quantities of iodine.
The great fallacy
Many people who want to lose weight use the following reasoning:
If thyroid hormones are so important and a thyroid deficiency caused by lack of iodine in the diet can make metabolism slow and sluggish and make people gain weight, then it must be true that people who are overweight will be able to speed up their metabolism and boost weight loss if they take thyroid hormones and massive doses of iodine.
True or false?
False. Taking synthetic thyroid hormones like eltroxin when you have normal thyroid function but are overweight, will not make you shed those kilos.
Why does it not help to take thyroid hormones in such cases?
If you have normal thyroid function and you take additional thyroid hormones, the body decreases thyroid hormone production so that the levels of thyroid hormone in the body remains unchanged.
The danger associated with taking thyroid hormones when you don’t need them, is that prolonged suppression of the thyroid gland may cause it to shrink and stop functioning altogether. To make such a "switched off" thyroid gland start working again may take quite a while.
In addition, people who take thyroid hormones hoping to lose weight often develop all the unpleasant symptoms of an overactive gland, such as:
- Heat intolerance
- Increased appetite
When you are trying to lose weight, the last thing you need is to feel nervous and ravenous - both conditions that make you less likely to stick to your diet.
Well, what about taking extra iodine?
Although adults need about 150 micrograms of iodine a day, taking more in the form of kelp tablets, see weed extract and iodine drops, can have a toxic effect on the body and should be avoided.
What should I do if I suspect that I have an underactive thyroid?
If you suspect that you have an underactive thyroid, do yourself a favour and consult your doctor first. Have thyroid function tests done and let the doctor decide if you have an overactive or underactive or normal thyroid gland. If your doctor prescribes thyroid hormone to assist an underactive thyroid gland, well and good.
If you have a normal thyroid gland and are overweight, then you will have to look at other cures for your problem. It is a sobering thought that 98 percent of all cases of obesity are not linked to ‘classical’ hormone problems (underactive thyroid gland, female hormones, etc.). A ‘new’ hormone called leptin, which is manufactured by the fat cells may prove to be involved with weight gain and reduction, but the thyroid is not often implicated in common obesity.
People gain weight because they eat the wrong foods, or too much food and don’t exercise enough. So don’t put yourself through added agony by demanding thyroid hormones from your doctor if you don’t need them - eat a Low-fat, High-fibre diet and go out and do some aerobic exercise on a regular basis and you will lose weight.
Remember that nowadays table salt is iodated in South Africa and that moderate use of this salt will basically ensure that no one in our country develops common, iodine-deficiency goitre anymore. Just note that I used the word "moderate" when talking about how much salt you eat. This is because excessive salt intake is also not good for you and can lead to high blood pressure, and kidney damage. - (Dr I.V. van Heerden, DietDoc)