June 25, 2008

Details: The "Big Breakfast Diet" was Low Carb & Very Low Cal

There's been a lot of ignorant coverage of the supposed benefits of a high carb big breakfast for dieters.

Now Diabetes in Control has published the details of this study and they are quite different than what the media coverage would suggest.

Here are the pertinent facts:

1. The specific of the diets (emphasis mine):

The low-carb diet allowed 1,085 calories a day with 17 grams of carbohydrates, 51 grams of protein, and 78 grams of fat. Breakfast for members of this group was to be 290 calories with 7 grams of carbohydrates and 12 grams of protein.

The modified form of this diet allowed 1,240 calories a day with less total fat (46 grams) but more carbs (97 grams) and protein (93 grams). The main feature was a 610-calorie "big breakfast" accounting for about half of the daily carbohydrates (58 grams), protein (47 grams), and fat (22 grams).

2. So as you can see, both diets were both technically low carb. But the first version is TOO low carb. The carb intake on that diet is so low that it is not possible for dieters eating it to eat the healthy low carb greens and vegetables which are essential to eating a healthy low carb diet.

That "low carb" diet does not match the description of any of the low carb diets that long term low carbers eat. Even Dr. Bernstein--the most stringent of all the low carb diet gurus--allows his dieters 30 grams a day of carbohydrate with possibly another 6 gram snack and recommends eating those carbs in the form of low carb vegetables.

3. These diets were also very unhealthy because they were extremely low calorie. The dieters were eating at a level so low that they were likely to depress their metabolisms. This guarantees weight regain.

Moreover, the "low carb" diet had 14% less calories than the other diet, a significant difference quite capable of explaining the result independent of the meal composition.

The beauty of the low carb diet is that it makes it possible for obese people to lose weight while eating a lot more calories than is possible on other diets.

The weight regain suffered by the so-called low carb dieters may have been the usual rebound suffered by any dieter eating under 1200 calories a day. That the two diets had different calorie intake levels should make any result attributed to dietary composition suspect.

3. This study was done in normal people and the carb loading technique it explored is not suitable for people with diabetes. This is because people with diabetes are most resistant to insulin in he morning thanks to dawn effect. That means they would end up with very high blood sugars after such a high carb meal which would result in a blood sugar swing that would make them very hungry by lunch time, tempting them to eat more.

4. This was not a peer reviewed study. It was a "poster session" at a conference where the researchers briefly described their research. This means that the quality of the research still has to be assessed.

If there is any value to the finding here--which is questionable, it might be that eating more early in the day can help prevent the after dinner snacking that derails so many dieters. Unfortunately the poor design of this study makes it hard to know if it really proved that.

You can test the idea in your own diet by moving some calories to breakfast from lunch or dinner and seeing if it makes you less hungry. Make them fat or protein calories, though, as a high carb breakfast is guaranteed to make you hungry unless you have rock solid normal blood sugar!


Lili said...

Wow, that's nuts! Have you told Dr Michael Eades?

Sue said...

The calories don't add up correctly as pointed out by Dana -the low carb diet plan adds up to a total of 974 calories.

ItsTheWooo said...

I don't know what the fuss is about; it's been shown before in studies that eating extremely low carb and low calorie diets will cause metabolic slow down. This makes for inefficient fat loss and efficient/easy fat regain due to the physiology and psychology of starvation.

I can't exactly say I expected the results, but I'm not exactly surprised, either.

Anonymous said...

It seems as though the study was set up for low carb to fail and look bad.

Alcinda (Cindy) Moore said...

Hi Jenny!

"This is because people with diabetes are most resistant to insulin in he morning thanks to dawn effect."

Is this true for all diabetics? I thought it was just for some.

Jenny said...


From what I've read, just about everyone is more insulin resistant in the morning. That is pretty clear in the CGMS study Dr. Christensen presented which is described (and linked) on my What is a normal blood sugar page.

The normal people's blood sugar went up much higher at breakfast than at meals with the same carb content later in the day.

Melissa S. Green said...

Actually, the problem with the "low carb" diet wasn't so much its low calories, as that it had insufficient protein -- only 51g. But low calorie/low carb diets called Protein Sparing Modified Fasts (PSMF), which feature sufficient protein which "spares" the protein stores of the body (i.e., muscle), have been used with great success clinically in treatment of obesity. Without sufficient protein, as in the diet used here, yes: muscle will be wasted, & the dieters set up for easier fat gain when the diet ends.

Jenny said...

The protein sparing modified fast is very good at taking off pounds, but because it is so below the basal metabolic rate, people tend to regain dramatically as soon as they get near goal.

I'm a big fan of slow weight loss at calorie levels that don't make you crazy, because with my own weight loss experience I've learned that I have had to eat pretty much at the calorie level I was eating at at the very end of my diet to maintain.

So if you lose at 800 calories, you may have to eat at 1000 to maintain. Not a good idea.

I lose 18% of my starting weight at 1450 and maintained at 1650 which is just doable.