Has Dieting Ruined Your Metabolism?
Have you ever tried — or wanted to try — to lose weight by doing something a little more extreme? Whether it’s a radical diet, fasting, cleansing, or juicing, these types of weight loss programs tend to be successful in the short-term – which is what makes them popular. But (and hopefully this will dissuade you) they don’t have a positive effect on metabolism — which is what you want for weight loss — and are harmful in the long run.
Extreme weight loss methods
One of the most common ways to fast-track weight loss is to go on a radical diet, by consuming only very low calories, replacing meals with drinks or protein shakes, or just extreme dieting. The problem with this method is you’re not going to live like this for the rest of your life, so building up healthy eating habits is more important, says Dr. Danhua Xiao, a Nutrition Physician Specialist at the Metabolic Weight and Wellness Center of Overlook Medical Center in Summit, NJ.
“Too rapid weight loss will do harm to your body,” says Dr. Xiao.
A detox type of diet that involves drinking a whole lot of juice and little else may cause dehydration, an electrolyte imbalance, protein deficiency, or even kidney insufficiency and blood clot formation due to severe dehydration, says Dr. Xiao. This method lets you lose water, but not fat, so it’s not real weight loss – and it’s not healthy.
Juicing – in which juice is extracted from fresh fruits or vegetables – contains concentrated sugars and most of the vitamins and minerals, Dr. Xiao says, but the healthy fiber is lost. Harvard University conducted studies that found an increased risk of Type 2 diabetes when juiced fruits were involved. Eating whole fruits helps lower cholesterol levels, but juicing doesn’t have this effect.
Of course, extra sugar and calories in juice can lead to weight gain. The American Cancer Society says there’s no evidence that juicing is healthier than eating whole foods.
“There is no scientific evidence showing [the above mentioned methods] can help people lose weight for the long-term,” says Dr. Xiao. “Some may even do harm to the human body.”
Weight loss from these extreme methods are due to the breakdown or loss of lean body tissue, explains Trish Lieberman, MS, RD, LDN, Director of Nutrition at The Renfrew Center in Philadelphia, PA. This means your body is breaking down muscle to give your body energy. Just because the number is going down on the scale doesn’t mean your body composition is changing, she cautions.
Dieting, fasting, cleansing, and juicing may contribute to uncomfortable and potentially dangerous side effects like fatigue, irritability, cravings, and headaches in less severe cases. Caloric restriction may also lead to decreased immunity, making it harder for the body to fight infections and illness, says Lieberman.
Plus, in the long run, the majority of people who lose weight using these methods regain it all back, and more, Lieberman says. She cites statistics that show that about one to two out of three people who go on a diet and lose weight regain more weight over the next four to five years than they initially lost.
Another effect from these diets is risk of dangerous low blood pressure, which can elevate your risk for an abnormal heart rhythm, says Dr. Kerstyn Zalesin, M.D., Bariatric Medical Director-Division of Nutrition and Preventative Medicine at Beaumont Hospital, Royal Oak, MI.
There definitely is a rebound effect after the diet ends. Rebound weight refers to the weight someone gains after losing weight through dieting, explains Lieberman. This is seen in scientific studies and in every day practice, she adds.
The mind wants to lose weight, but the body tries to fight it because there’s an energy deficit, which Lieberman describes as a war between the mind and body’s physiological needs. “No matter what the cause of the weight loss, the body sees it as if you are starving and will adjust your metabolism in attempt to keep your weight within your ‘set point’ range,” she says, “just like a thermostat adjusts to keep the temperature the same.”
Because extreme dieting promotes the wrong kind of weight loss via mostly fluid losses, water weight is quickly regained once the diet is over, says Dr. Zalesin. “To make matters worse, after extreme dieting, appetite is increased and cravings soar, making it even harder to stay on track commonly resulting in weight gain,” she says.
Impact on metabolism
Would you be shocked to learn that none of these methods affect metabolism in the way you want? “Staying on an extreme diet will negatively impact your metabolism in the long run because your body senses the effect of starvation and protects itself by slowing your metabolic rate,” says Dr. Zalesin. “This slowed metabolic rate will in turn make weight loss more of a challenge.”
Women at risk
The experts agree that women are more likely to resort to extreme lengths to lose weight. Not only are we “held to a higher standard in terms of our weight, but self esteem and a heightened awareness of body image promote cultural pressures and bias that affect women disproportionately,” says Dr. Zalesin. Therefore, “the focus on achieving a desired goal weight creates higher levels of desperation and a greater willingness to believe false claims or dangerous promises of weight loss outcomes that fad diets offer.”
Lieberman has some interesting statistics. She says roughly 50 percent of women and 25 percent of men in the U.S. are currently on a diet. More damning is that 85 percent of people using weight loss products and services are women.
“Weight control is a lifetime journey,” says Dr. Xiao. “There is no easy way, no magic diet or magic pills. Diet and exercise are always the most important. [If necessary,] go to a specialized weight loss program with a board-certified obesity medicine specialist and lose weight in a healthy way.”