Up and down

Yo-yo dieting means restricting food intake drastically and losing weight very quickly only to go back to eating as you did before, thus putting all the weight back on and then some.

A survey in 2014 found that 60% of yo-yo dieters will try up to 20 different diets in their lifetime... repeat offenders!

But this constant up and down has health consequences that go far beyond your waistline.  Extreme diets have been blamed for many health problems such as hormone imbalances, osteoporosis and even heart problems.

So, what does yo-yo dieting really do to your body?

To start with is the one we already know, you'll put it all back on again and then some more.

Studies have shown that the body strives to maintain its weight at what is called a set point.  The body will protect itself against weight loss during a period of restricted intake, which also explains why people often don't put weight on if they over eat for short periods of time.  However, when the body is being starved for a fairly long period of time, weight loss occurs but your body also gets used to functioning on less resources.  When this happens, your metabolism gets reset to that lower level, so when you start eating normally again you put the weight back on faster.

However, diets like the 5:2 diet, which involve intermittent fasting, do not reset the metabolism as the period of calorie restriction is too short.

When calorie intake is severely restricted, there comes a point when the body begins to digest its own muscle cells as well as remaining fat cells for energy.  Muscle mass is actually esencial for weight control as in order to maintain muscle the body burns more calories.  So, if your body is obliged to digest muscle this will actually slow metabolism even more and promotes rapid fat gain when you begin to eat normally again.

It's aging.

Depending on how much weight you lose, your body can be left with stretch marks, saggy and
droopy skin.  Also, the more this happens the worse the consequences as you age.  As we get older our skin loses elasticity.  Older women will be more prone to saggy skin.  Less drastic weight loss regimes where the weight comes off gradually, give the skin time to adjust.  Also restrictive diets can have an affect on the plumpness of skin especially if the diet has a low protein content.  This stops the production of collagen which gives the skin its firmness.

Yo-yo dieting can also affect the health of your hair.  At any one time, 90% of head hair is in a growth phase and just 10% is in the resting or shedding phase.  Restricting calories severely forces more hairs into the shedding phase as the follicles have fewer nutrients to sustain them.  Rapid weight gain also affects normal hormone levels and stresses hair follicles.

Severely restricted calorie intake means the body isn't getting as many key vitamins and minerals such as calcium to keep their teeth and gums healthy.  Yo-yo dieters are more prone to gum disease which can also lead to tooth loss.  Dieters who severely restrict their food intake produce less saliva.  The saliva produced in the chewing of food helps protect the teeth against acid attack.  And when they reintroduce lots of food into their diets they tend to choose a high carbohydrate diet which puts them at risk of tooth decay.

Heart Unhealthy.

In the latest study from the Memorial Hospital of Rhode Island, data from 158,000 women over the age of 50 was analyzed.  Dr. Somail Rasla, lead author of the study, says that gaining weight as part of  yo-yo dieting increases heart rate, blood pressure, cholesterol and blood sugar levels.  These alterations do not go back to normal when the weight is lost again.  With the up and down of repeated yo-yo dieting, these problems only get worse over time, damaging the heart in the process.

The study which was carried out over an 11 year period, showed that women of normal weight who admitted to yo-yo dieting more than four times, were three and a half times as likely to die from a heart attack than women whose weight was stable, even if they were obese.

Yo-yo dieting also increases inflammation markers in the blood which are associated to lots of diseases such as arthritis.

Fertility Treatment Problems

Calorie restriction followed by bingeing can disrupt the release of hormones from the pituitary gland which drives the menstrual cycle, stimulating the ovaries to release eggs.

When a woman loses weight quickly, this process shuts down because the body switches to starvation mode and diverts all its energy to vital processes and reproduction is not considered a vital process.

However, many women are told to lose weight in order to qualify for fertility treatment, and this can encourage crash dieting.  It has been found that women who lose weight as quickly as possible, sometimes reducing their calorie intake to 400 calories a day, in order to reach the required weight for treatment, have very poor outcomes when it comes to getting pregnant as the IVF is unlikely to work.

Losing weight sensibly through lifestyle changes is much healthier and the weight stays off.  It's up to you what you want for your body and your health.

I can help you improve your health.  If you would like to make an appointment with me either in person or via Skype, just send me an email to lucycarr@socialnutrition.com