Will cutting calories make you live longer?
No, but it will seem longer.
That’s my attempt at a joke. But maybe it’s not a joke. Maybe it’s true.
For many years there’s been an idea—derived initially from animal research—that restricting caloric intake makes a person live longer. Here’s a report on the latest findings, which are based in part on a study with a pretty Draconian design for its subjects. I certainly hope they were well-compensated for this kind of suffering:
Pennington is one of the few places in the world with these hotel-room-sized microenvironments, the most rigorous way to measure how many calories a person burns and where they come from””fat, protein, or carbohydrates.
After a night of fasting, participants entered the calorimeter promptly at 8:00am, and until 8:00am the following day they weren’t allowed to leave or exercise. Researchers delivered meals through a small, air-locked cupboard. As fresh air circulated into the room, the air flowing out went through a series of analyzers to measure the ratio of carbon dioxide to oxygen. Nitrogen measurements from urine samples help calculate a total picture of each participant’s resting metabolism.
Sounds like fun, doesn’t it? The findings were as follows:
…[C]utting calories, even modestly, lowered people’s metabolism by 10 percent. Some of that could be attributed to weight loss (on average folks lost 20 pounds over two years). But according to the study’s authors, the majority of the change had more to do with altered biological processes, which they observed through other biomarkers like insulin and thyroid hormones…“After two years, the lower rate of metabolism and level of calorie restriction was linked to a reduction in oxidative damage to cells and tissues.”
On reading that, one of the things I noticed is that it may validate the observation many dieters (and would-be dieters) make that dieting lowers one’s metabolism. This makes it more difficult to lose weight, not easier, because the same amount of food is used more efficiently by the body, although of course if the calorie restriction is big enough weight will be lost nevertheless. But a calorie restriction of 25% (that’s what was done in the study, amounting to 500 to 800 calories less per day), strictly held to over two years and resulting in a 10 pound per year weight loss, is just another indication of how difficult it is for many people to lose a very significant amount of weight. One would think the loss would be more, if you go by the old idea that 3500 calories of reduction leads to a pound of weight loss. By those calculations, the subjects should have lost far far more weight than they did.
But was the diet worth it in terms of health advantages? Do reduced metabolism and “a reduction in oxidative damage cells and tissues” make up for the deprivation? The study wasn’t long enough to determine the answer. Researchers differ:
Fontana’s own work with Calerie trial data suggests changes to specific insulin pathways matter more than overall metabolism decrease. He also points to studies where rats were made to swim in cold water for hours a day, dropping their metabolism. They didn’t live any longer than room temperature rats. In other studies, scientists overexpressed enzymes that protected mice from free radicals. They didn’t live any longer either. Redman’s data is interesting, he says, but it’s not the whole picture. “Twenty years ago the dogma was the more calorie restriction the better,” he says. “What we are finding now is that it’s not the number that matters. Genetics, the composition of the diet, when you eat, what’s in your microbiome, this all influences the impact of calorie restriction.”
That’s certainly been my personal experience, which of course is merely anecdotal.
To my surprise, that joke I made at the beginning of this post was echoed at the end of the article about the research:
Jeffrey Peipert [is a] 58-year-old ob-gyn [who] participated in the Washington University trial nine years ago, hoping to bring down his weight, which he’d struggled with his whole life. When he went in, his blood pressure was 132 over 84; after a few months on a restricted calorie regimen it dropped to 115 over 65. A year in he lost 30 pounds. But six months later he quit. It was just too much work. “It took away my energy, my strength, it definitely took away my sex drive,” says Peipert. “And tracking calories every day was a total pain in the neck.”
Today he’s gained all the weight back and has to take a pill for hypertension. But at least he feels like he’s living well, even if he maybe won’t live as long.
I know that the Taubes people will come out of the woodwork and say they’ve got the answer. I would like to caution them that, while I’m glad that way of eating works so well for you (and more power to you!), that sort of approach not only does not result in weight loss for me and for many others, but there are those of us who find we feel physically bad on the diet, too.
Different diets seem to suit different people. Each person needs to find the best balance for him/herself. That’s a cliche, but it seems true. Some people with “good” health habits die young, and some with “bad” health habits live a long and happy life. The rest is statistics, but most of us don’t plot our entire lives by statistics.
I need to live another 20 years in order to see Creighton in the Final Four. But I will never live long enough to see the Cornhuskers in the Final Four.
It is depressing to read the calorie burn of what seems like serious exercise. Swim hard for half an hour and that’s half a Krispy Creme.
Still, I talked with a tri-athlete who said, that, when in serious training, he could easily eat six thousand calories a day. (I can do that without training). It would stand to reason, then, that if he ate five thousand calories, he would shortly die of starvation. Or have to quit training.
It is difficult. But if you keep your cookies and crackers around the house to a minimum, you might save a couple of hundred calories a day. There’s a kind of low-level craving you would feed if it were easy but not if there were any effort to it. You’d eat a cracker. But you wouldn’t go out and by a package, nor make up a batch.
the medical model is so wrong no one even looks at it to fix it
i have had discussions and have shown that their model does NOT match reality..
and the things your mentioing from caloric restruction to a kind of immortality if you could stop the dings of outrageous fortune (started by the man who invented the nuclear bomb – not einstein)
tons of stuff
but even a cursory glance at their model and what is known would show its not even close.. and they just ignore it.
i worked out the math, but im a nobody
and ramanujans era is over, so dying in obscurity is best
cant wait
really..
with what they have done to me at work and now, i cant wait.
I have been on quite the journey lately in an effort to be able to run a full marathon and to lose some weight. I am over 50 and found that with the onset of menopause, I was rapidly gaining weight. I had been running 4 to 6 miles every few days but had not changed my diet and was unable to lose weight. I read Taubes and tried many things but found that a Ketogenic diet worked well for a while for me. However, after a while, I once again was unable to lose weight that I needed to lose in order to be able to run faster and longer.
After several years of frustrating diets that seemed to come with weight gain, I finally broke down and consulted with a sports dietitian. She evaluated what I like to eat along with what my goals were. My goals were modest….lose a little weight (maybe 20 or so lbs) and be able to survive running a full marathon within about 4 months. She noted that I was still mostly doing a ketogenic diet but put me back on certain carbs (beans, winter squash, root vegetables, colored potatoes with skin, oats, berries, small apples and oranges) I still got most of the same protein and fats but she did ask me to cut back the amount of bacon that is prevalent in keto diets and to add more nuts and seeds for fat. I also experimented with things to eat while on long runs to see how my stomach would tolerate them and had to make sure to consume a lot of water with electrolytes and salt sticks.
I did manage to run\walk my first full marathon this year. It was difficult and I think I need to do more to help myself get through it better. However, along the way, I have lost about 15 lbs with most of that loss from loosing body fat, lost 5% of my total body fat, gone down inches in nearly every part of my body and down 2 clothes sizes so far. I feel like I may be down another size but am afraid to test out that theory. To top it all off, I feel like I am starving all the time now when before I used to not be hungry but would eat anyway. I am taking care to eat good carbs and other things and seem to not be gaining weight despite eating a LOT lately.
Since my full marathon I have run another half marathon (that makes half marathon #14 over 8 years) but am finding that my body needs a rest from running. I was logging what I eat for the dietician but have lapsed on that for the past 2 weeks. Logging food is a huge pain in the neck but I will restart my logging so that I don’t fall too far off the wagon during my break.
I feel like my story is a study in how diets work for some and not others. And I finally had to consult with a specialist who listened to me to get things right. Hopefully what I am doing now will keep having benefits and get my weight down even further. What I want to leave off with is that if anyone here is struggling with their weight, please find a dietician to work with. I was very skeptical that I would get much out of my engagement but am very pleased and will likely re-engage with her this fall when I start training for my next marathon.
I got interested in calorie restriction after reading the book by Roy Walford. Average lifespan extension by calorie restriction with optimal nutrition has been shown repeatedly in studies from nematodes to recently higher primates like rhesus monkeys. See for example this Scientific American article
It is not sufficient just to reduce calories, you have to do it with a diet that provides the nutrients your body needs. And of course it does not lead to immortality. It does extend average lifespan by “squaring up” the mortality curve. Practically that means you stay healthy until shortly before you die–not the steady decline that most people have.
To get the full benefit, the suggestion is to find the number of calories, again with full nutrition, that keeps you at your weight set point and then drop 10-15%. That’s too much for me but I have managed to stay at my set point. I am in my late 60’s and weigh as much as I did in my 30’s. A lot of that is probably genetics but I have found that if I eat restaurant or frozen prepared food I gain weight.
I look at it like something I read in a book about test pilots. They could not control things going wrong but if they went down they did it while doing the things that they were supposed to be doing.
First of all 50+ years later, I weigh 2 pounds more than when I graduated from HS. I have a high metabolism which helps, plus I eat and usually drink with moderatio, and now that my new knee has healed, I walk 3 miles a day. I say this not to brag, but to note weight problems usually result from too many calories and not enough exercise.
However, there are exceptions. We are not born equal.
Slow the burn. Go green. There are supplements for that.
If someone said, start using Meth and once you’re good and hooked, we’ll see if we can cure you of it, you’d probably think it was a crazy thing to do.
The point is, you shouldn’t have to be cured of it, because before you tried it there was no problem.
I’m afraid the best solution is to never be introduced to anything but healthy foods.
Before I started anything, I never suffered from missing it, whether it was cigarettes, or candy bars, or soft drinks. I didn’t have a problem with any of those, I developed it.
I did well with Tim Ferriss’s “The 4-Hour Body Diet” — four small meals a day of protein, veggies and beans, but nothing high-glycemic (sugar, flour, fruit). Slow-carb in other words.
It was pretty boring but you also got one day per week to go wild and eat anything you wanted. The idea was to prevent your body from lowering your metabolism in response to dieting. I lost about 20 lbs in three months.
Then my life went crazy for various non-diet reasons and I didn’t get back to it.
Here’s a flaw that I see in the above…
When attempting to reduce one’s weight, the proper approach is not ‘either/or’ but ‘both/and’.
I combined lowered calories with an increase in exercise. This allowed me (I think) to kick my metabolism up a smidge, or at least not let it drop. I found that weight training did help. An increase in muscle mass in theory increases your daily calorie burn. It may not matter that much in the short term, but certainly over time I think it may help.