Sunday, August 9, 2009

Low carb a self fulfilling prophecy?

Interesting ideas:

The health benefits of a gluten-free diet might also be a kind of self-fulfilling prophecy. It's well-known that our digestive system adapts its secretions (rather quickly) to whatever we're eating. A prolonged stint on the Atkins diet, for example, can make it harder to digest starchy foods. According to a 2006 study in Journal of the Pancreas, a colony of lab rats subsisting on low-carb, high-fat food pellets ended up with less pancreatic α-amylase, an enzyme that helps break down complex carbohydrates. Now imagine that you've cut out gluten from your diet completely—that means no bread, no cereal, no wheat whatsoever. Chances are you'll have reduced your total intake of carbs, and thus the amount of α-amylase in your gut. In other words, the mere fact of being on a gluten-free diet could make you more sensitive to grains and cereals—which would only reinforce your conviction that you're gluten-intolerant. Slip up for even one meal, and you'll pay the price with indigestion. (Same goes for people who don't eat meat or dairy: A momentary lapse can yield a nasty stomachache.)

Hat Tip to Seth

I've experienced that. Go low carb for a while and you can no longer cope well with carbs. Even if you used to be able to take them , you now struggle to tolerate them....and they seem unhealthy!

The rest of the article and its analysis is interesting although I'm not sure I'd agree with it! I do think that refined carbs (pastas, flours, breads etc) are not natural and we will not thrive on them.

4 comments:

skylark said...

I've experienced both sides of dietary exclusion effects and have had a different experience.

After being ovo-lacto veg for 12 years, I decided to begin eating meat. Upon eating my first meat-based meal, I anticipated a great degree of discomfort to follow. I experienced none at all, either then or during subsequent meat-based meals.

After excluding all grains from my diet for 6 months, I ate a grain-based dinner. 12 hours later I was on the floor in my bathroom, in tears, clutching my stomach. It took hours for the pain, discomfort and bloating to pass.

pieter d said...

Seems logical. Stress an organism and it will react as good as it can. Take away the stressor and the adaptation will go away.

This sounds familiar. Lift weights your body, and it will adapt (e.g. hypertrophy of the muscle). If you then for a longer period do not lift weights, then muscle wasting occurs. And of course, if you then lift heavy weights, it will hurt...

Unfortunately, this doesn't tell us if the stressor (and the amount of stress) is healthy!

Stress your organism with lots of carbs, and it will try to adapt as good as it can. Insulin resistance and metabolic syndrome as a consequense...

How do you say this in English: my 2 cents??

Pieter D (from Belgium)

L. Wu said...

Did you see this blog entry?

http://www.fitnessspotlight.com/2009/08/03/carb-diets-overrated-part-ii-kitavan-okinawa-diets/

Clamence said...

This is a lot of clever hand waving at best.

I.

Did anyone read the linked study? Over 48 weeks they fed rats a "low carb diet" with 12.3% of kcals from carbs, and compared them to a control who consumed 50.3% of their kcals from carbs.

Oh, and the experimental group ate an additional 1900 Kcal/kg per day (6510 kcal/kg for the 'low carb' vs 4610 kcal/kg for the control).

Great, so what did the authors find? A 25% reduction in intracellar amylase while eating 75% less carbs. Oh and a insignificant relationship between basal and cck stimulated secretory amylase and lipase activity.

II.

Daniel Engber has confused gluten free with carbohydrate free.

People who don't eat meat or dairy get a stomachache when they do, as they dramatically increase their intake of that particular food.

There are plenty of gluten-free carb sources (rice, potatoes, squash, corn). If someone who thinks they're gluten intolerance can not discern eating 2-5x the amount of carbohydrates they usually consume with eating gluten, I have little hope for their ability to make intelligent dietary decisions.

III.

It is unclear how much of the popular actually suffers from celiac disease, or is gluten intolerant. 20-30% of people with the HLA-DQ2 allel do not have celiac disease, and about 5% of celiac patients do not have the HLA-DQ2 allel.

Mr. Engber seems satisfied to attribute the effects of a gluten free diet to paying attention to what you eat and the placebo effect.

IV.

Seth Roberts umami hypothesis that he references in the post linked as "hat tip to seth" is ridiculous.

"To avoid stomach cancer and high blood pressure, I later cut back on miso, kimchi, and smelly cheese.". Right, like the menaquinone in these things doesn't reduce your heart disease risk. Please read The Rotterdam Study.

"As for meat-, fish-, and dairy-grown bacteria, I don’t think they are very dangerous." Right...and what are mycotoxins?.

"I keep in mind how much stinky fish the Eskimos ate. Maybe I should do some controlled rotting experiments — leave meat at room temperature for varying lengths of time before cooking and eating it.". Sounds like a great way to make yourself sick. Way to confuse fermenting fish in a region of the world with almost continuous permafrost.