A bad function of the thyroid can cause weight gain for no apparent reason (and also a loss) you’ve probably heard it many times.
But do you know exactly how this gland works to be so determinant in this respect?
To overcome doubts, we interviewed Noelia Martínez Sánchez, a researcher specializing in endocrinology at the Gulbenkian Institute of Science (Portugal).
This gland is always related to weight but… is this because of thyroid hormones that accelerate or slow down metabolism, or do they also affect the appetite?
It is true that these hormones control many metabolic processes. Especially…
They increase the basal metabolic rate, that is, the energy you consume to keep the body at rest.
And this activity is so important that it “manifests” right away when you have thyroid disorder.:
Thus, hyperthyroidism (characterized by an overactivation of the gland and therefore by an excess production of thyroid hormones) causes more oxygen and more energy to be consumed and more heat produced, which increases the metabolic rate (your body “accelerates”) and leads to weight loss and tachycardia.
Thyroid hormones directly influence your metabolism
At the other end, in hypothyroidism, where levels of these hormones are reduced, there is more sensitivity to cold, a decrease in energy expenditure, weight gain despite eating less… In fact, 20% of obese patients suffer from hypothyroidism.
Many of these effects are linked to the direct action of this hormone on the liver, fat, muscle, and heart.
But now there is evidence that they also influence the brain, which may also affect metabolism and a greater appetite for food or not.
Do these hormones also affect the fat composition of the body?
Of course. Note that they are very important in the energy balance, which is just the balance between the calories you consume and those you spend.
When this balance is positive, that is, you eat more than you burn, it increases the risk of obesity and fat accumulation.
But thyroid hormones can stimulate fat metabolism and increase your energy expenditure. In particular, what they do is increase the activity of so-called brown or good fat, a type of fat that (unlike white or “bad” fat) makes you consume more energy and therefore lose weight.
It seems that exercising stimulates brown fat.
If the thyroid is altered, can it also raise triglyceride and cholesterol levels?
That’s right. There are many studies that show that people with hypothyroidism have high total cholesterol in their blood, as well as triglycerides.
And it is that these hormones regulate the synthesis of cholesterol in our organism through multiple mechanisms, but mainly by exercising its action in the liver.
Subclinical hypothyroidism (which gives almost no symptoms) is common in middle-aged women. What signs can make us suspect?
Logically, because it is subclinical it usually does not give symptoms, if the typical signs of hypothyroidism (fatigue, somnolence, muscle weakness, depression, weight gain, decreased heart rate, etc.) appeared, we would stop talking about subclinical as such.
But it is true that more non-specific signs such as:
Mild tiredness and weariness.
A slight intolerance to cold that could be confused or simply associated with different stages in a person’s life such as stress situations, overwork, increased activity, etc.
There’s a type of hypothyroidism that doesn’t give any signs.
Therefore, the best diagnosis is through laboratory tests, that is, with a blood test evaluating TSH levels and thyroid hormones.
The most affected are women over 55 years of age, so the doctor should be consulted to monitor these signs.
Is consuming iodized Marine salt the simplest and most effective way to prevent thyroid disturbances?
Iodine is an essential component of thyroid hormones and its deficiency affects the production of these hormones and has adverse effects especially during pregnancy because it affects the baby’s cognitive development and growth.
However, recent epidemiological data suggest that iodine deficiency remains a problem in many countries and is a key determinant of thyroid disorders in adults.
When Iodine requirements are not met, thyroid hormone synthesis is affected, which can lead to hypothyroidism, goiter, neurological disorders…
Therefore, making appropriate consumption of this element, for example through iodized sea salt, is one of the key and preventive strategies to reduce thyroid disorders.