CALERIE: The NIH Calorie-Restriction Experiment. Lessons for Health, Slowing Down the Aging Process, Longevity, and Disease Prevention

Photo credit: Reinhard Hunger NYT 10/11/09

"In terms of cardiovascular diseases - the No. 1 cause of death; 4 out of 10 people die of it in the U.S. and Europe - we know that they (Calorie Restriction Society members) will not die of cardiovascular death."

"... subjects have cholesterol around 160, blood pressure around 100 over 60, high HDL, low triglycerides and very low levels of inflammation."

"...every day doctors are publishing  hundreds of papers on circulation research  and medications that are lowering blood pressure or cholesterol by a small bit.  And here we have such a powerful intervention that is basically cleaning out the arteries."

"I don't know why anyone would take drugs when they could do something like this." 

Dr. Luigi Fontana & Dr. Susan Roberts, Washington University & Tufts University investigators for the NIH- funded CALERIE Study,   NYT 10/11/09

If you had the chance to stay healthy and lean as you aged--free from the diseases of aging, like diabetes, cancer, and cardiovascular diseases--and all you had to do was cut out 25% of your daily calorie intake--would you do it?  Oh--and if you could also fit into cool clothes, drop to your high school weight,  & enjoy super energy?  Would you be willing to do it?

We know that careful calorie restriction--eating a nutrient-dense-low-calorie diet--works in rodents and those University of Wisconsin rhesus monkeys--but will it work for humans who are constantly tempted by cheeseburgers, pizzas, office parties, and dinners out with friends?  (Read about the Rhesus Monkey 20 year follow-up here)

According Dr. Susan Roberts, one of the principal CALERIE investigators, when it comes to animals,  "They don't just live longer, they are healthier.  They actually aged biologically slower.  Their hair has gone gray less quickly.  Their hormones have stayed at their youthful profile and their immune function has stayed good."

I'd heard for years about too-skinny "calorie-restriction groupies" who were out to beat death with a miserably low-cal boring diet.  It held no appeal for me.  I love food too much!

But, I've got to tell you, after reading about the National Institute of Aging's ongoing calorie-restriction  experiment known as CALERIE  (Comprehensive Assessment of Long-Term Effects of Reducing Intake of Energy)--I'm rethinking this whole calorie-restriction scene!  This is not excruciating or boring at all!  And since I started on my "veganish" adventure in March of 2008--I'm not that far away from the CALERIE model already!

Take a look at Jon Gertner's fascinating story, "The Calorie-Restriction Experiment" in the October 11, 2009 New York Times Magazine, here. 

Honestly, I'd describe it as Weight Watcher's on steroids--with help from physicians, dietitians and counselors.  There's even room for an occasional Uno's pizza, Haagen Dazs ice cream bar, bratwurst, or beer.

The first participants are finishing up their 2-year trial and the results are promising.

What is the CALERIE Study?

• Since it's virtually impossible to follow people over a lifetime to find out if restricting calories by 25% would slow aging, drastically reduce diabetes, cardiovascular diseases, and cancer--CALERIE aims to follow a select group (right now there are 132 enrolled) for two years to find out if the biomarkers for aging can be modified when calories are restricted.
• The study will measure if inflammation, insulin levels, blood pressure, core body temperature, and body weight can be lowered simply by reducing calories by 25%.
• Where are the sites?  Tufts University in Boston; Washington University in St. Louis; Pennington Biomedical Research Center in Baton Rouge.
• Who is eligible?  20-50 year olds who are healthy and not too fat or too thin--having a BMI of 22-27.9.  Participants also have to be motivated, organized (they have to measure & record every morsel they eat for 24 months), have stable jobs with little travel, and a supportive family.

What's the Diet Like?

• So, do you think you know how many calories you eat every day?  Think again.  Most participants guessed wrong.  Using a high-tech lab technique that involves swallowing water with rare isotopes, the researchers are able to figure out precisely how many calories each participant is typically consuming.  Then they cut it down by 25%.  
• Liz Ewen, a molecular biologist, was eating 2,226 before CALERIE--now she's at 1,670.  Dr. Jeff Peipert, an OB-Gyn, was consuming a whopping 3,300 a day pre-CALERIE--now he's at just under 2,500. 
• For the first 28 days participants get all their meals & snacks cooked for them and at no cost--based on their individual calorie counts.  This gets them accustomed to portion sizes and adjusted to eating the kind of foods that will keep them filled and satisfied.  And this food isn't spartan:  Mediterranean-style fish with Greek-style potatoes, or Farfalle with Pesto & Diced Chicken, for example.  After 28 days--they buy and prepare their own food--with regular help and guidance from dietitians and a support group.
• The Key to eating 25% less:  eat foods that are nutrient rich and high in fiber, like vegetables, fruit, high fiber cereals, and soups.  Aim for foods that weigh as much as what you were eating before the diet--but lower in calories--to keep you full and satisfied.  Favorite food for keeping hunger at bay:  apples.   Everyone in CALERIE has become a big fan of apples. 
• The 4 Rules for Eating Less:  Eat Foods That Are Filling, Appealing, Low in Calories, Nutrient Rich!
• Dr. Susan Roberts of Tufts says, "If you don't change your diet to a high-satiety diet you will be hungry, and you will fail."  Fiber One, the breakfast cereal, or Nature's Path Organic Smart Bran--both with soluble & insoluble fiber, "have a unique  effect in helping calorie-restriction subjects feel fuller, probably because they activate certain receptors in the lower intestine."

To see some of Dr. Roberts' satiating snack recipes in my previous post click here: "The Instinct Diet Helps Us Combat Our Hard-Wired Food Cravings - And Satisfy Our Cravings for Something Spicy, Salty, Crunchy, & Chocolate"

• CALERIE tip: Save up calories if you have a special occasion or celebration coming up.  Want a bratwurst or Haagen-Dazs?  Save up those calories.  Decide what's more satisfying--170 calories for a gin & tonic, or a  190 calories for a  Haagen Dasz ice cream bar.

What Is the Hardest Part of the CALERIE Diet?

• Surprisingly, no one complains of raging hunger.  Bu most everyone felt hungry for the first few weeks.  When I joined Weight Watchers years ago to lose pregnancy weight I felt exactly the same way.  But then you just get used to less calories and learn to eat more filling foods.
• The hardest (& most annoying) part is getting used to measuring the food, preparing the food, and keeping track of the calories.

Why is CALERIE Working For Most of Its Participants?

• There's accountability. 
• You have to submit a weekly food diary.
• Attend weekly weigh-ins
• Once or twice a week you must attend individual counseling sessions
• Group counseling sessions give participants an opportunity to swap strategies and get support from fellow dieters.
• There's a battery of medical tests every 6 months.  Cognitive tests.  Blood tests.  Bone-mineral density tests.  Measurements of resting metabolism, respiratory output, and internal core temperature.

What About Weight Loss?  What About Health Improvements?  What About Energy? 

• Most participants met their weight loss goals.  They were told to expect to lose about 15% of their weight during the first year.  After that initial drop they would plateau to "weight stability".
• Doug Hansen started out at 198 pounds and dropped to 168--near his plateau--after 6 months.  Jeff Peipert began at 174 pounds--dropped to 151 after 52 weeks--and was projected to plateau at 147 pounds.
• Benefits.  For example: Peipert's blood pressure started out at 130 over 80.  Now almost a year into CALERIE, he's at 110 or 115 over 54. At age 49 his weight is what he weighed in high school.  Same for Brad Beggs. He is down to wearing a size medium shirt--a size he hasn't worn since high school.  And Beggs adds, "I've never gotten so much pleasure in my life."

Dr. Jeff Peipert, a Washington University CALERIE participant

• Wondering about energy?  Check out how Dr. Jeff Peipert spent a recent day off:

1.   18 holes of golf

2.   Biking 8 miles back & forth to his office just to pick something up

3.   Cutting his 1 acre lawn

4.   Pulling out tree roots with his son for over an hour

5.   40 minute after-dinner walk with his wife.

6.   This "calorie-incinerating machine"  was wondering why he felt particularly hungry the next day,  resulting in his eating a bowl of cereal in the middle-of-the-night.  Both my husband & I have definitely noticed the huge uptick in our appetites the day after long work-outs.  It makes sense to us.

Is Calorie-Restriction Possible for the Average American?

• The Naysayers:  Dr. John Holloszy, a Washington University lead investigator thinks 99% of Americans can't stick with it.  Other doctors think calorie-restriction requires too much individual effort--too much in medical resources--too much in counseling.   Dr. Robert Krikorian, a neuropsychologist who happens to be a long-time follower of a calorie-restriction diet himself-- thinks that most people won't pay attention to how much they eat--and they would refuse to keep up the organizational requirements necessary for such a diet.
• The Boosters:  Many doctors involved in CALERIE are surprised & encouraged at the high level of compliance with the diet.
• The Participants:  All of the subjects that Times writer Jon Gertner spoke with intended to continue with calorie-restriction when the trial ended.  Liz Ewen likened it to Weight Watchers (& I agree).  Given the right online tools, some sort of infrastructure, group meetings, and dietitians available for support, Ewen thinks it's suitable for many people.  "It's really not much more than embarking on a diet that teaches you how to eat normal foods but make better choices!"
• Some of the  first of the group to finish:  Most of "first finishers" plan to keep up the diet--but switch to estimating the calories, rather than counting them precisely.  Josh McMichael finished up with CALERIE in September.  In the few weeks since ending the program he gained eight pounds--but it's now mostly gone.  "I tried the new massive burgers at Burger King,"  he said.  "Twice.  Wasn't worth the side effects.  I think I've gotten over things like that.  For the most part."

Words of Encouragement from the Lead Investigators

• Dr. Luigi Fontana of Washington University in St. Louis.  "My perception right now is the effects of calorie restriction are multiple, so I think it is highly difficult to find one, or two, or three drugs that will mimic such a complex effect."  And although he isn't optimistic that calorie restriction will gain traction in the general public, he does believe an important common sense lesson will be learned from the experiment:

"Eating less is better than eating more, especially if it's a nutritious mix of whole grains, fruits, vegetables and the like.  The evidence is overwhelming now that it will improve your health and will improve your chances of living healthier and probably longer."

• Dr. Susan Roberts of Tufts University in Boston:  Roberts thinks the study will have greater effects than the average clinical trial.  "I don't know why anyone would take drugs when they could do something like this--calorie-restriction,"  said Roberts.

The Healthy Librarian Weighs in on Calorie Restriction

For my money, the folks in the CALERIE study are following a plan that seems very similar to:

• Dr. Joel Fuhrman's Eat for Health: Lose Weight, Keep It Off, Look Younger, and Liver Longer
  
• Dr. Susan Roberts'  (a CALERIE lead investigator) Instinct Diet
• Dr. Caldwell Essestyn's Prevent and Reverse Heart Disease
• The Weight Watcher's diet plan

Easiest way to cut calories:  ditch added fats, like butter, margarine, mayo, cooking oils, salad dressings, desserts, high-fat dairy like cheese & ice cream, and the after-dinner snacking.

Foods highest in nutrient density:

*Dr.Fuhrman’s  Aggregate Nutrient Density Index
Top 30 Super Foods Score

1. Collard, mustard, & turnip greens 1000
2. Kale 1000
3. Watercress 1000
4. Bok choy 824
5. Spinach 739
6. Brussels sprouts 672
7. Swiss chard 670
8. Arugula 559
9. Radish 554
10. Cabbage 481
11. Bean sprouts 444
12. Red peppers 420
13. Romaine lettuce 389
14. Broccoli 376
15. Carrot juice 344
16. Tomatoes & tomato products 190-300
17. Cauliflower 295
18. Strawberries 212
19. Pomegranate juice 193
20. Blackberries 178
21. Plums 157
22. Raspberries 145
23. Blueberries 130
24. Papaya 118
25. Brazil nuts 116
26. Oranges 109
27. Tofu 86
28. Beans (all varieties) 55-70
29. Seeds: flaxseed, sunflower, sesame 45
30. Walnuts 29

Drugs or Diet?  I find it interesting that the only cure for celiac disease (the inability to digest gluten) is to follow a gluten-free diet.  There are no pharmaceutical or surgical cures.  People with celiac who want to get better just follow a gluten-free diet.

Yet, when it comes to the diseases of aging, like Type 2 diabetes, some cancers, and cardiovascular diseases--most physicians find that the majority of people are unwilling to follow a diet even if it promises to free them from these diseases.  Oh well!

Do you think such a diet is ready for Prime Time?  Would you be willing to give it a try?

Comments

[Rick]

Another great post - thanks! To be scientific about one's approach to this diet, you need to know your baseline, and as you mentioned, everyone guesses too high. If you're not a part of a study, how would you ever figure this out? Once you have your magic number, then you have to be systematic in recording your food consumption, which means calculating what the calories all come to. Not the hardest thing in the world to do, but harder to do then flossing your teeth, and plenty of people skip that.
I think this would be most likely to be undertaken by those of us can glimpse our immortality either through dint of age or prospective health issues. That said, it is very intriguing to me...if I could get a baseline, I think I would give it a shot.

[Tomer Guez]

> You have to submit a weekly food diary.

A good addition to this is a very good program I have been using, Food And Exercise Diary (WeightLossSoftware.Com). It is a food diary, medical diary, and exercise diary. Lots of functions.

[Kim]

I read the article in the Times this morning, and your blog post this afternoon. I started doing a vegetarian low-carb regime, but couldn't hack no meat, so added eggs, chicken breast, tuna & salmon. I found that most of the foods I'm eating are on this list! All I would need to do is rethink the fats, and I am so doing.

[Thomas]

I pretty much already follow such a diet (Esselstyn & McDougall). Mostly because I don't want exploratory open heart surgery.

[Anders]

I do miss Spirulina on this list.

[Hank Roberts]

I grew up on collard, turnip, and beet greens and love them; but back in the 1950s, cooking greens was a little different -- there was a little bucket by the stove for pouring bacon grease out of the skillet in the morning, with a filter on the top to catch the crunchy bits, and that was used the rest of the day for all kinds of cooking, including the greens.

Recipes needed ....