Pregnancy Nutritionist Explains How Yo-Yo Dieting Affects Fertility

In the New Year, many begin new regimens, diets, weight-loss programs, and exercise programs. Many of these New Year plans include intense exercise and extreme calorie restrictions. Results are quick, but, we can get ensnared in a resolution trap, and our bodies and health end up paying a heavy price. Wanting to be healthy is a great thing! But buying into quick weight-loss programs isn’t the road we should take.

Weight cycling is the repeated loss and regain of body weight that can range from 5 – 10 pounds per cycle up to 50 pounds per cycle. When this weight loss occurs during dieting, it’s referred to as  yo-yo dieting. Yo-yo dieting  is one of the biggest side-effects of the New Year.

There are some serious health implications for yo-yo dieters – most because of health problems related to being overweight or obese, and others because of the act of the body losing and gaining weight, quickly, in cycles, takes its toll.

Cardiovascular Disease: Obesity is directly linked to heart disease. It’s the number one cause of death for both men and women in the United States. Healthy weight means a healthy heart. Yo-Yo dieters have an increased risk of heart disease and blood pressure.

Metabolism: Metabolism varies from individual to individual and fluctuates in life during pregnancy or the loss or gain of muscle. But to get significant calorie expenditure, you have to significantly increase muscle. Burning calories during cardiovascular exercise is different. It doesn’t build muscle and permanently elevate metabolism, instead, metabolism is elevated for a number of hours after cardio depending on the duration and intensity. Our bodies need calories to keep our metabolism going. Our bodies’ natural reaction to starvation (extreme calorie restriction, fewer than 1000 calories each day), will be to turn their metabolism down. Again, this isn’t permanent, but the effect of a yo-yo quick loss will also be lowered metabolism and, in turn, lowered energy levels.

Increase of our primary stress hormone cortisol: When our bodies are exposed to stress (whether it be through extreme calorie restriction, work, or life stress), our bodies release our primary stress hormone called cortisol. Our bodies’ machinery is so elegant because this physiological response is what keeps us safe during moments of extreme stress, increasing glucose (sugar) and fat in the bloodstream and curbing non-essential s during critical periods,  alternating our bodies’ systems: immune system, reproductive system, growth system and digestive system. Normally, our bodies re-adjust and go back to normal. But under extreme, constant stress, cortisol remains, and our bodies can experience: anxiety, digestive problems, heart disease, sleep problems, weight gain, and memory and concentration problems.  Read more about chronic stress from the Mayo Clinic.

Fertility and Yo-Yo Dieting: Many women struggle with becoming pregnant. While being a healthy weight before getting pregnant is important, yo-yo dieting could be affecting your chances of conception. Yo-yo dieting affects ovulation. Many women with PCOS go undiagnosed and struggle to lose weight, getting caught in weight cycling traps … essentially putting a bandaid on a problem instead of getting to the root cause. Fluctuations in weight and calorie intake can cause a woman to become insulin resistant which, then, reduces her chances of fertility.

Obesity has become a health epidemic in the United States. We support initiatives for change and being healthy. It’s essential to take the right steps toward healthy weight loss and maintenance, we’re not doing our bodies many favors (not to mention our self-esteem). It shouldn’t be about a number on a scale, but instead about wellness.