Womens' cholesterol level varies depending on phase of menstrual cycle

Some interesting new research published in the Journal of Clinical Endocrinology and Metabolism has found that a woman’s cholesterol level fluctuates quite a bit during the month. Cholesterol is quite sensitive to the female hormone estrogen, and as levels of this hormone fluctuate, so too does cholesterol.

This particular study compared estrogen levels with cholesterol and triglyceride levels in 259 healthy women aged between 18 and 44 years. On average, their cholesterol level varied by 19 percent, depending on where they were in their menstrual cycle. That is quite a significant variation.

The researchers discovered that as estrogen levels rise, so too does HDL (“good”) cholesterol. Levels of HDL peak just before ovulation. You want your HDL to be as high as possible, because it transports cholesterol away from your arteries, to your liver. As your estrogen level rises, your total cholesterol, LDL (“bad”) cholesterol and triglycerides fall. This effect is not immediate though. Therefore, the researchers found that overall levels of blood fats are lowest shortly before menstrual bleeding begins. Overall levels of blood fats are highest shortly before ovulation. You may want to keep this in mind the next time you have a blood test.

It has been known for some time that the estrogen in hormonal contraceptives and hormone replacement therapy affect a woman’s cholesterol level, but researchers were not aware that our own body’s estrogen has such a profound effect on blood fats. Pre-menopausal women are far less susceptible to heart attacks and strokes than post-menopausal women, and it is thought that higher estrogen levels are one protective factor.

Of course, hormones are a fairly minor factor affecting your blood fats compared to your diet. The majority of the cholesterol and triglycerides in your body were manufactured in your liver out of sugar, carbohydrate rich foods and alcohol. Eating a lot of those foods will raise your blood fats. If you have sluggish liver function, if you are stressed and if you carry excess weight in your abdominal area, you are also at risk of having high blood fat levels. Even having an under active thyroid gland can cause elevated cholesterol.

For information on natural ways to keep your cholesterol in check, see our book Cholesterol the Real Truth.

Source: National Institutes of Health