A high-fructose diet—the type of sugar found in fruits—can result in metabolic and cardiovascular damage, such as insulin resistance or heart failure.

Although both men and women can be affected by this, some studies suggest that women may be protected against these damages by the presence of female sex hormones.

“Finding the mechanisms behind this protection is one of my research goals,” says Julieta Palomeque, a research professor at the Unit of Experimental Medicine of the Institute for Obesity Research (IOR), in an interview with TecScience.

While fructose found in fruits is not harmful to health, as it comes with fiber and other nutrients, when extracted and used to create syrups that sweeten various products, such as soft drinks and desserts, that’s when problems start.

In an industrialized world, fructose syrup is present in a large percentage of foods sold in supermarkets and stores. Studies, such as the one published in The American Journal of Clinical Nutrition, have found that excessive consumption of these products causes some of the damages observed in people with obesity.

To elucidate the cellular and molecular mechanisms that lead to these problems, Palomeque and her team have studied the effect of a high-fructose diet in animal models.

Same Diet, Different Results

Initially, they studied it in males and found different cardiac and metabolic alterations, such as hypertrophy, cell death within the heart, increased triglycerides and lipids in the blood, and insulin resistance.

“Later, I was interested in seeing what happened with females, as women are very different from men biologically,” explains the researcher. According to her, they expected to observe similar damages but with different molecular mechanisms.

However, they found that the same high-fructose diet, previously tested in males, does not cause metabolic or cardiac alterations in females of reproductive age.

“It would seem that women are protected from these damages, at least in animal models,” says Palomeque.

When observing these results, they wanted to test if female sex hormones, such as estrogens, were involved in this protection.

To study this, they used a female animal model whose ovaries were removed and, therefore, the production of estrogens. One month after the extraction, they started using the high-fructose diet to see what happened.

They found that this lack of estrogens, combined with the diet, produced an unfavorable metabolic state, similar to that observed in males, but did not cause complications in the heart.

With these results, their idea is that the sex hormones involved in the protection against heart damage could be those generated by the pituitary gland—better known as the pituitary—or the hypothalamus—a region of the brain involved in various functions.

The interaction between the hypothalamus, the pituitary, and the ovaries produces sex hormones, such as estrogens, GnRH, LH, and FSH, which are involved in the female menstrual cycle and ovulation.

“My conclusion, so far, is that estrogens are necessary for metabolic maintenance in females, but they are not involved in cardiac protection,” says Palomeque.

How It Would Help Women During Menopause In the Future

The researcher seeks to study if these other sex hormones could play a role in why females in reproductive age do not have heart complications with a high-fructose diet.

For the expert, understanding the mechanisms behind this protection could help explain why older or menopausal women suffer more from obesity-related damages.

“It has been observed that, after menopause, women gain weight and have a higher incidence of metabolic damages, such as diabetes and heart events,” says the researcher.

While her team continues to elucidate these mechanisms through basic science, Palomeque warns that it is important to focus medical efforts on preventing obesity and the damages that come with it, as well as the effects of menopause.

After the age of 50, women should undergo routine check-ups to monitor their hormone levels and risks of heart events, Palomeque adds.

Overall, as humanity, we must be aware of the changes that come with age and strive to have good eating habits, exercise, and maintain a healthy mind before aging.

“We must be attentive to our checks and our care to age fully,” she recommends.