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Prolactin is the cause of excess weight
Medical expert of the article
Last reviewed: 04.07.2025
This hormone is produced by a small part of the brain – the pituitary gland. It is prolactin that can be the reason why a woman gains extra pounds. Most prolactin is produced when a mother breastfeeds her baby, because prolactin controls the level of milk in the mammary glands. Then the nursing mother can begin to actively gain weight.
[ What you need to know about prolactin?
Know that if a woman is not pregnant, the level of prolactin in her body will not be higher than 20 ng/ml. The same amount of prolactin is normal for a man. But as soon as a woman becomes pregnant, the level of prolactin steadily increases.
In the last months of pregnancy, it can reach 300 ng/ml. When prolactin in the body becomes more than 20 ng/ml, menstruation may be irregular, or, if prolactin levels increase, stop altogether.
What are the risks of increased prolactin production?
This condition may be accompanied by milk leakage from the nipples, as well as headaches, irritability, and bad mood.
By taking hormone tests for prolactin levels, you can determine whether you are pregnant and whether you should be prescribed hormone therapy.
Once a mother has given birth and begins breastfeeding her baby, prolactin levels drop compared to the last trimester of pregnancy, and it becomes easier to control your weight.
Prolactin can also be a cause of excess weight because it can suppress the female hormone estradiol, which controls metabolic activity in the body.
Bone tissue may be compromised (bones become brittle), skin may lose its elasticity and sag, and hair may begin to fall out. These are all signs of high prolactin levels.
Prolactin and age-related changes
Prolactin increases in the body when a woman begins to experience age-related changes. Metabolism slows down, due to the increased level of prolactin, which affects fat deposition, it is increasingly difficult to control weight, even if you torture yourself with diets.
Causes of elevated prolactin levels may include:
- Menopause and pre-menopause
- Age-related changes after 40
- Stress
- Increased physical activity
- Under-dosed stay in the gym
- Uncontrolled use of medications, especially psychotropic drugs
- Constant stimulation of a woman's nipples
Consequences of high prolactin levels
If the pituitary gland produces too much of this hormone, a person's vision, memory, and general well-being may be significantly impaired. The reason for this is that formations in the pituitary gland can physically press on the optic nerve and thus impair the functioning of the eye.
If you notice similar symptoms, contact an endocrinologist for a prolactin test. A blood test done between 07:00 and 08:00 will provide detailed information about the level of this hormone in the blood. Then the endocrinologist will be able to prescribe the best treatment for you.
In this case, you will be able to improve the production of prolactin in the body, then it will be much easier for you to control your weight and well-being.
Be healthy and contact professional doctors in time!