Nutrition

Diets work, but low carb doesn't improve insulin sensitivty

Published 9.12.2017
A collection of (relatively) recent interesting links relating to nutrition, none of which warranted its own piece.

Diets don’t work if you don’t/won’t follow them. This is Katz, with all the usual caveats. Despite all the noise on the internet, there is decent nutritional knowledge out there. A diet consisting of mostly plants is generally best (I'm not a doctor, but I’m sure there are conditions that would counterindicate a mostly plant diet).

Don’t let the perfect be the enemy of the good is what he’s saying. We don’t know the details of everything, but we do know enough to describe a healthy diet. Katz is addressing at people attacking the dietary guidelines. People don’t eat as the dietary guideline prescribe, so you can’t say the guidelines don’t work.

Food companies do exploit the guidelines, and always will. Is that a reason not to have them?

More confirmation bias paraded here. Never ever does she discuss increasing insulin sensitivity. The low carb answer is to keep blood glucose levels low by not ingesting carbs. For heaven’s sake, here she acknowledges that carbs are more than just grains— but even vegetables are to be avoided.

No, 1000 times no. And naturally no mention of legumes. Go ahead and skip the bread and other grains. But greens and beans and other vegetables are high are full of vitamins, minerals and phytonutrients— you know, the foods that would mean you won't need to pop supplements if you would only eat them.

High fat diets might keep blood glucose low, but it does nothing to increase insulin sensitivity. Increasing insulin sensitivity also lowers insulin levels, because less insulin is needed to get the glucose into the cell. Insulin sensitivity is the downfall of the low carb treatment.

The issue here isn’t skipping breakfast, it’s eating at 11 PM. Valter Longo’s work suggests that eating in a shorter window (8 hours vs 12-16) better suits the body’s circadian rhythms.

Eight healthy, normal-weight adults (age 26.25 ± 3.2; BMI 22.39 ± 1.9; four women) participated in the randomized cross-over study in free-living conditions with two phases: daytime eating (three meals and two snacks consumed between 8 a.m. and 7 p.m.) and delayed eating (three meals and two snacks consumed between noon and 11 p.m.)

Subjects slept 7 hours starting at 11PM, which would suggest that some of them were eating right before going to bed. Supposedly they ate similar diets— but it does not say that calories were controlled.

Goel noted that a 24-hour hormonal profile showed that during the daytime eating period, the appetite hormone ghrelin peaked earlier in the day, while the satiety protein leptin peaked later, suggesting that eating earlier in the day helped the participants to stay satiated longer.

If you’re talking about satiety issues, then the intake levels were different. If you’re not satiated, you tend to eat more.

Marketing is how to get people to eat more vegetables?

Dishes with the "indulgent" names were taken by 25%-41% more people in the cafeteria than those with the less effusive descriptors, and the mass of vegetables taken was higher by 16%-33%. In most comparisons, the increased popularity was statistically significant.

This is one demonstration, and it might not translate to other settings. However, it’s a low cost solution, so by all means I support it being tried. However, I also think preparing vegetables in tastier ways is also an avenue worth exploring. Too often, vegetables are simply steamed, boiled or stir fried and plopped on the plate. Rarely is there any spice or saucing involved. There are far more creative ways to cook vegetables.

The trend of chef’s setting up restaurants centered around vegetables should help this cause.