For the past two years, I've been a participant in a medical study called CALERIE. The point was to measure what happens to a person (specifically, their metabolism and how fast their body ages) when you restrict the amount of calories they eat.
Research on this topic began in the early 80s, and it has since been proven pretty solidly that lifespan increases and illness decreases when calories are cut. Primitive organisms were the original experimental model, and then mice (I believe they cut the calories by 50%), and then when that worked they moved on to larger animals. Here's an article explaining a study that began in 1989, following monkeys with a diet restricted by 30% of normal calories. They've been studying these monkeys 20 years now, pretty much just seeing how long before they die... and it's a long time. The findings have been pretty incredible - a multitude of benefits seem to be associated with eating less.
In fact, there are people who already voluntarily restrict calories in attempt to live longer. It used to be a fringe trend, starting in the 90s, but now it's more mainstream. Most of the people dedicated to this lifestyle look like skeletons to me... but hey, maybe that's worth it if you live longer...?
So this CALERIE study was designed to test the aging/calorie link in humans. The goal was to create a calorie deficit of 25% of each subject's normal consumption (any more restriction than that was deemed unsustainable in reality, and too difficult on the subjects). There are two ways to create a calorie deficit (which means you consume fewer calories than you burn). One is to eat less, and one is to burn more calories. Phase I of the CALERIE study was a six-month study, and they tried three methods of calorie restriction. Method 1 restricted food by 25%, Method 2 added enough exercise to create a 25% deficit, and Method 3 was a combination of less food and more exercise.
At the end of Phase I, they found out that it's very very hard to exercise enough to burn 25% more calories than you normally do. Say, two hours in the gym. Every day.
Unsurprisingly, that method was very hard for people to stick to.
The combination method (more exercise and less food) still required people to spend about an hour in the gym, as well as diet. That also turned out to be difficult, and complicated logistically. So they settled on the food-only method. I would argue that it's still very difficult to do, but at least it's less time-intensive, and simpler to keep track of, and overall the most efficient method of calorie restriction.
So enter Phase II of the study, a two-year commitment to eat 25% less than you normally do. I signed up for the study, made it through the screening process, and was randomly assigned to the restricted group (as opposed to the control group, who really lucked out because they got paid the same amount for not changing a thing about their eating...).
At the beginning, I thought it was going to be easy. "They're paying me for this?" I thought, "and all I have to do is write down what I eat, and cut out the chips and cookies? Well bring it on!"
For the first month of study, they provided me food to eat. They do this to help you start the new habit of eating less - the meals they provide are sized to the amount of calories that you are allowed (or, your "calorie prescription" they call it). So you don't have to worry about calculating anything, you just eat the prepared food. I missed having chocolate (not part of the prepared meals...) but in general, it was easy peasy.
And life was going fantastically. From April to June, (two months) I had gone from my starting weight of 180 to a weight of 165. I felt better, I looked better, and what wasn't to like? By November (seven months), I was down to 160. I was on track, I weighed just what I was "supposed to." I was in the proper "weight zone" on the graph. According to the study directors, if I stuck to the 25% restriction, I should settle out at about 152 in a couple more months.
Now I have to tell you people, I have never weighed 152. Maybe for two weeks once when I was 12, as I rushed past that number during a growth spurt. So I was always skeptical that I would get to that weight. But I had no reason to doubt it - the trend line was going that way.
But here is where it fell apart.
In January of 2010, ten months in, I stopped losing weight after hitting a low of 157. I also started to really feel the pressure of recording everything that I ate. For someone so data-driven as I am, having to know and be aware of the calories of every single bite going into my mouth really bothered me. I never had to control my calories or my weight before, and having to control that area of my life was really making me become obsessive.
And also once I stopped losing weight, I went outside the approved "weight zone," because I was still supposed to be losing weight to get down to 152. So then every time I went to the study office to weigh in, I was told I was overweight. Hearing that for months in a row really started to influence me as well.
So it got really hard, really quick. But I am nothing if not an overachiever, so I tried really, really hard to stay on track.
I am ashamed to say that I would just not eat - I'd decide to basically starve myself rather than see a number on the scale that was too high. In fact I recall a time that I didn't eat for five days. But dang it, that number was correct when I weighed in on the scale.
The problem with that, as you may have guessed, is that it is unsustainable. Even if you don't eat, the weight you lose is mostly water, so you gain it right back when you start eating again.
Then I was in a quandary. I had to weigh in once a week. I knew from experience that I lose at a rate of two pounds a day if I don't eat (and the fact that I know that, is a testament to how badly I let this study mess with my head). So do the math - if I'm eight pounds overweight, I have to not eat for four days before weigh-in. If I was six pounds overweight, I had to not eat for three days. Now I kept thinking to myself, "I'll just get down to that weight and they STAY THERE, so I won't have to do this again." But as I said, you go right back to your previous weight because the loss isn't real - it's only water.
So do the math. Fasting for three days to make weight, then weigh in. Eat normally for three days, go right back up to previous weight. But recall that you have to weigh in every week - so you have four days left until next weigh in. And so then you have only one more day to eat before you have to start fasting again.
You can imagine this did not end well.
The turning point came one particular morning, and I remember it clearly. I woke up, and I really didn't feel very good. But I went to study headquarters anyway to weigh-in. I stepped on that scale, talked to the nutritional counselor as usual for a little while just to check in, and left early because I was feeling worse. On my way out of the building, I stopped to use the bathroom and get a drink of water. I just felt so tired and dizzy, so I went in the handicap stall and laid down on the floor. Twenty minutes later I looked up and realized that I must have fallen asleep.
Right then I realized I was being ridiculous. Of course I didn't feel well, and of course I passed out on the bathroom floor - I hadn't eaten for three days. And before that, I had only eaten for four days, because the week earlier I had done the same thing. I was putting my body through the wringer - and here's the catch - for NOTHING. Because all I could think was that the number on the scale was still too high.
Ladies and gents, we have a problem.
I am too smart to not see what was happening. When I stopped enjoying food, when I started thinking of my meals in 100-calorie increments, when I started feeling guilty for eating, when I started weighing myself twice a day compulsively, when I would eat junk food and be in tears while eating, when I would specifically say no to outings with friends because I'd have to eat high-calorie foods - these are not healthy things.
Trying to cut my calories by 25% created an eating disorder, plain and simple.
So in September, around the eighteen month mark, I called it quits. My weight had bounced around a bit, and I was back at about 163. So in total, for all the frustration I put myself through, I weighed essentially no differently than I had the previous November.
Ugh. SO not worth it.
I am pleased to say I have dropped as many unhealthy habits as I could. I weighed myself once a day as required, but no more. I stopped writing down everything I ate, and refused to feel guilty for eating. I never starved myself ever again.
Even though I had decided not to worry about restriction anymore, I still continued with the study. They can still use the data, after all. And so since I was still involved with the study, still weighing in every two weeks, it was still always in the back of my mind. I still knew the calories in things, I still cooked with lower calories in mind, I still always had a niggling feeling I was failing. Failing because without trying to restrict my calories, my weight started to creep up. From the 163 last September, I am 169 as of today. Still, I'd like to point out, that is down from the starting weight of 180, although nowhere near the fantasy eating-disorder-creating "goal" of 152.
And today - well, today is a beautiful day.
Today I am officially done with the study. Yesterday was my last day as a part of the study, and I was released from the hospital where I had to stay for two nights for testing at 8am this morning.
It's only appropriate that I end with a graph. Here is my weight, taken almost daily for the past two years. Highlighted points are the starting point of 180 on April 30th 2009, low point of 157.4 on December 9th 2009, and ending point of 169.0 today April 13th 2011. In the middle, around days 430-530 (June - September 2010) you can see the wild swings that occur when you misguidedly try starving yourself...
I am so, so thrilled to be done. Even though for the last six months, and really for the last year, I haven't been following the 25% restriction, I still have had to deal with the mental and emotional aspects of this study. Had I known what this would be like, I never would have signed up. Maybe given some time, I'll have a different perspective and can see the benefit, but for now I just have to give a hearty "take a hike" to the whole experience.
Evidence from monkeys or not, longer life is only useful if you enjoy the living. Carpe diem, and pass me a brownie!