Archive for May, 2011

A calorie is a calorie, unless of course they derive from an Atkins diet

May 10th, 2011

The newest issue of Consumer Reports compared various popular diets based on how they match up to the the USDA dietary guidelines, as well as how successful they are. Coming as a surprise to many, the Atkins diet seemed to perform the best. Here is their chart (red means good, black is bad. Whole circles are better than half circles):

If a calorie is a calorie, regardless of what macronutrient it comes from, then how is it possible that the Atkins diet allows the most calories, yet they boast the best short term and long term weight loss results? Consumer reports took an average of meal plans for two weeks on each diet (taken from the published books) and found that on average, an Atkins diet suggests eating over 1900 calories per day, while the Zone and Ornish suggest eating 1260 and 1525 respectably.

According to traditional logic, if you want to lose weight, there must be a calorie deficit. In other words, you should find out how many calories your body uses each day, then eat 500 calories less each day and you will lose 1 pound per week. According to (which employs the widely used mifflin-St Jeor basal metabolic rate equations), for a 5’3″ 160 pound woman to lose one pound per week she should eat about 1480 calories a day. If this person went on the Atkins diet summarized in Consumer Reports, they would be predicted to GAIN a pound each week! And those consuming the Zone diet would be predicted to lose the most weight since they allow the least calories per day.

Yet this doesn’t seem to be the case. In this review of diets and the scientific literature supporting them, calories don’t predict weight loss.

This seems to be an unspoken consistent finding in the scientific literature. I have summarized this exact topic, with a link to all the recent studies in our research library.

If calories don’t predict weight loss, then what does?

To try to explain these findings, or any other weight loss questions, as Gary Taubes points out, we should figure out three things:

  • What does “getting fat” mean?
  • What regulates our fat cells?
  • Is there anything we eat that modifies or enhances the effects of these regulators?

Of course getting fat means having more fat in your fat cells. The more fat that is stored in your fat cells located under your skin, the fatter you become. Next, we would want to find out if there is anything that causes the calories we eat to be diverted into our fat cells for storage as opposed to used by the body for energy? And the answer is yes. It is a hormone called Insulin. When insulin is high, calories are stored as fat. If it is low, calories are released from fat cells for energy.

This is uncontroversial. Any biochemistry textbook can explain this in depth.

The million dollar, controversial question then becomes: If insulin causes us to store fat in our fat cells, then does anything we eat cause insulin to spike?

Without a doubt, sugar or refined carbohydrates tend to spike insulin the most. Carbohydrates in general spike insulin levels. Protein does too, but too a lesser degree. So assuming this theory is true, then a net reduction in sugar and carbohydrates in your diet should result in more weight loss regardless of how many calories you are eating. This does seem to be true in the report above, since the Atkins group ate the most calories and the least carbohydrates. This also is suggested in dietary clinical trials, in which the various diets report eating the same amount of calories, yet the Atkins group seems to lose the most weight.

The next counter argument tends to be that a diet so high in saturated fats is bad for your heart. Here is how Consumer Reports explains this concept:

Isn’t it dangerous to eat so much fat? That’s still a subject of vigorous scientific debate, but it’s clear that fat is not the all-round villain we’ve been taught it is. Several epidemiology studies have found that saturated fat doesn’t seem to increase people’s risk of cardiovascular disease or stroke. Other studies suggest that you might be even better off if you replace saturated fat with unsaturated fat instead of with certain carbs, the ones that turn to blood sugar quickly after you eat them, such as white bread and potatoes. A nutrition researcher, Frank B. Hu, M.D., of the Harvard School of Public Health, recently wrote that he believes “refined carbohydrates are likely to cause even greater metabolic damage than saturated fat in a predominantly sedentary and overweight population.” Moreover, clinical studies have found that an Atkins or Atkins-like diet not only doesn’t increase heart-disease risk factors but also actually reduces them as much as or more than low-fat, higher-carb diets that produce equivalent weight loss.

There does not seem to be any strong evidence that saturated fats cause heart disease. You can read more about this here.

Nutrition and Weight Loss

Treadmill Desk!? Seriously!?!

May 1st, 2011

Treadmill Desk does not include a treadmill??

Sounding like another crazy infomercial, the Treadmill Desk is for real! The brainchild of Dr. James Levine of the Mayo Clinic, the idea is exactly what it sounds like. Walk on a treadmill instead of sitting in a chair while answering emails and writing code. The website is filled with outrageous claims, such as “lose 50-70 pounds in a single year” and “90% decreased risk of having an initial heart attack.” There are also 52 BENEFITS TO USING THIS DESK listed on their website:

1. Switches on the body’s metabolic furnace, allowing efficient calorie burning.
2. Treadmill desks stimulate the lymphatic system and wards off disease.
3. Stimulates brain function, improving memory as much as 15% in a 6 month period using a treadmill desk.
4. Increases blood flow to the brain and increases productivity.
5. Improves mood and wards off mild depression without medication.
6. Treadmill desks promotes significant weight loss and control of appetite.
7. Prevents onset of Type II Diabetes and assists with control.
8. A treadmill desk improves blood circulation throughout the body.
9. Improve lung capacity and strength walking with a treadmill desk.
10. Promotes healthy restorative sleep patterns.
11. Bolsters the immune system.
12. Treadmill desks prevent bone loss (osteoporosis).
13. Reduces the risk of coronary heart disease and stroke.
14. Treadmill desks reduce bad cholesterol (LDL).
15. Improves blood lipid profiles.
16. A treadmill desk increases good cholesterol (HDL) levels.
17. Walking at a treadmill desk reduces overall body fat.
18. Treadmill desks enhance mental well being.
19. A treadmill desk reduces the risk of colon cancer.
20. Walking with a treadmill desk may reduce the risk of breast cancer.
21. Reduces inflammation from arthritis and osteoarthritis.
22. Increases flexibility and coordination, reducing risks of falls.
23. Reduces the risk of dementia and Alzheimers.
24. Walking with a treadmill desk consistently INCREASES LIFE SPAN.
24. Relieve back pain walking on a treadmill desk.
25. Treadmill desks assist in recoveries after some surgeries.
26. Treadmill desks may reduce side effects of chemotherapy.
For the remaining list of benefits, click here.

I mean how can you not buy one now!? Here is Dr. Levine, describing his product to some excited reporters:

Lose 50-70 pounds a year? Where does he get this number from?

According to common logic, if walking at 1 mile per hour burns about 100 calories per hour, then if you walk for 8 hours a day for a year, at the end of that year you have burned 219,000 calories! Since 1 pound equals 3,500 calories, that means you would lose 62 pounds in one year! Trying to use this basic math equation to predict the complex process of human weight loss relies on one major assumption: That you will eat exactly as much as you did before walking 6 hours a day! It assumes that exercising and getting hungry (and therefore eating more) are independent variables. But anyone who lives in a city, or has walked an 18 hole golf course probably disagrees.

Later in the video, Dr. Levine says that just standing burns 20 more calories/hour than sitting. Then the reporter says that if you chew gum, that’s an extra 11 calories per hour! While it may take that much energy to stand and chew gum at the same time, if I were to say that you can lose 26 pounds a year by standing and chewing gum, It would be ridiculous.

But it is the exact same logic: If I stand (burns 20 extra calories/hour according to Dr. Levine) and chew gum (burns 11 calories per hour) for 8 hours a day, after a year I will have burned 90,520 calories and lost 26 pounds! So if this is true, why would anyone go through the hassle and social embarrassment of walking on a treadmill while checking your e-mail at work!?

This logic is fundamentally flawed. And wait a minute…this exercise at work idea sounds awfully familiar:

Nutrition and Weight Loss