Diets are hard. That is, going on a restricted calorie diet is hard, and not only because it takes a lot of willpower. From CNN Health:
Last year, Karen Daniel was feeling great about her weight. She had gone from 375 pounds to 200 in 24 months.
She was working out nine times a week and thrilled to have turned her life around. She no longer had to purchase two seats on an airplane. She went hot-air ballooning for the first time.
Daniel, one of Fit Nation’s first success stories, said in February 2009, “Fit feels so good.”
That feeling didn’t last long.
Daniel started feeling bad after a trip to New York. She had a sinus infection, upper respiratory infection and bronchitis, she said recently from her home in Arizona. She started feeling better, but then got sick again. And healthy again. And sick again.
She went to two doctors who told her that her body was in “starvation mode,” she said.
“I went way under on calories, and I got really sick,” she said. “I went to under 1,000 calories a day, and I was working out between two and three hours a day. It was not a smart decision.”
She felt like she was eating right, but she was gaining weight.
Ms. Daniel’s experience is not unique, and her tale rings familiar for many of us.
“Starvation mode” is a real phenomenon, although there are many myths surrounding it. Your doctor is probably clear on the issue: as the human body enters into starvation mode, it reacts by slowing metabolism, using up fat stores, then consuming muscle and other valuable tissue. Health effects from starvation mode include vital organ damage and increased infections as Ms Daniel experienced.
I have been critical of the “calories in / calories out” weight loss plans, mainly because counting calories is horrible proxy for determining how we metabolize food. But that doesn’t mean that we can’t use calories to measure the total amount of food a person consumes; we could also use the physical weight of food, the volume it occupies before being chewed, etc. The value of the calorie is that it has been standardized and everyone knows what it means. And we have an idea of how many calories we need to consume, on average, to maintain weight.
It is generally accepted that if you consume less than 50% of that maintenance level your body will enter starvation mode. If you require 2,000 calories a day, and you consume 1,000, you will, most likely, go into starvation mode.
Those that advocate very low calorie diets (VLCD) will explain part of this away. Studies show that even on lower-than-50% diets, the metabolic rate doesn’t slow to zero; it can slow up to 40%, as shown in the famous Ancel Keys study (where he “imprisoned” men and “starved them” in an experiment that would never pass muster with any medical ethics board today). So you will still lose weight, but at a slower pace. And, there is some evidence that you don’t start to seriously consume your muscle and organs until you fall under 5% body fat.
The problem, the advocates say, is that very low calorie diets work great, but people are bad. Its a little like making square tires for a car: they may be the highest quality rubber, with the best overall quality, but your car won’t go very far on them. Weight Watchers, in denying that starvation mode exists, says: “Over-restriction of calorie intake, known as high dietary restraint is linked to periods of overeating, hindering successful weight loss.” Well, they should know.
Diet plans like Weight Watchers, and others bound to fail, usually aim for a “calorie deficit”, with a reduction of about 25% of your normal intake, with the goal of losing 1 pound a week. There is some slowing of your metabolism as the body reacts to the lower food intake (actually, during the first 48 hours, the metabolism actually speeds up, and then slows down), but it isn’t as severe as the slowing in full-on starvation mode.
This slowing of the metabolism is temporary; as soon as you start eating your “maintenance level” of calories, the normal basal metabolic rate is restored. If, like Ms. Daniel, you have lost about half your body weight, the amount of food needed to maintain your weight is somewhat less. But habits die hard, and resuming the same food intake when you are finished with the diet has trapped many a dieter.
The transitory nature of weight loss diets, the “suffer until I reach goal” mentality, argues against long term weight loss and health maintenance. The yo-yo dieter follows a familiar pattern: extreme effort to exercise more, eat less, and then, inevitably “falling off the wagon” and eating like they always have. Or binging for a short time, only to face guilt and resumption of the low calorie diet. It is a vicious cycle that endangers health.
“Falling off the wagon” is not a moral failure; it is a biological imperative. You are starving, so it is time to get up, chase down an animal, kill it and eat. Eat until you are sated, eat all you can, and make up for the past days of low calorie intake. That’s how we are built. In designing diets based around the idea of starving the fat off of you, the advocates of this approach are working against at least 200,000 years of human adaptation to diet (and more likely, millions of years of adaptation).
A better solution is to avoid weight loss diets, per se, and focus on a new paradigm. A permanent change to the way of eating that benefits you the most is in order. Carbohydrate restriction is the easiest way for many to change their food outlook; in either The Protein Power Lifeplan or the New Atkins for a New You plans, you count only the grams of carbohydrates (restricting them) and the grams of protein (making sure you get enough), and don’t worry too much about the overall calories in the diet. Most people lose weight without hunger on a low carb way of eating.
Some people find a mind-shift necessary to counter-act all the bad dietary advice over the last 50 years. While both Protein Power and the The New Atkins are founded solidly on the most recent science, it is hard to ignore the headlines from the latest observational study that links saturated fat to obesity or health issues. For them, adopting a paleo or primal diet provides the intellectual framework they need: we have evolved or adapted to eat certain foods, and modern processed foods (including wheat and bread) have only been around about 10,000 years.