For some Greenlanders, eating sugar is healthy

This is not always the case. Be wary of assigning intent to a stochastic process like evolution. It's about probability, not certainty.

See: vagus nerve

"Imagine being able to swap out broccoli for sweets, Ben & Jerry's or some other sugary treat and achieve the same health benefits. This is fact not fantasy for about two to three percent of the Greenlandic population"

The study does not say sweets confer the same health benefits as broccoli!

Given that its pretty well known that high levels of sugar in the gut cause gut bacteria to go wild, a very reasonable research hypothesis would be to figure out why their gut microbiome is naturally deficient, such that turbocharging it up with a dose of raw sugar beings their gut microbiome activity up to normal healthy levels.

Sure dumping 2 liters of pepsi soda in their gut might cause all kinds of IBS like symptoms when their guts explode. But in the old days they just ate a couple berries once in a while, or at least the article claimed that.

This could be something as trivial as lots of fat intake means lots of bile production means some probiotic bacteria that's sensitive to bile suffers, until they eat a tiny amount of sugar that lets them grow to normal levels.

Could look at what gut bacteria do in stereotypical average humans. Gut bacteria under normal conditions do churn out some thiamine, folate, biotin, riboflavin, vit K, and probably stuff I'm not able to find from a quick search at pubmed central.

I think a really good research paper would combine the article results with a hypothesis that greenlanders as a group suffer (or, archeologically suffered, or occasionally suffered, or their kids suffered, etc) from deficiencies in folate, biotin, vit K, etc, basically the list above, and turbo charging their gut bacteria with a dose of raw sugar makes the bacteria more active which brings their vit K level or whatever up to normal human levels such that they're healthier on average and/or their kids die less often etc.

I didn't google up much immediately for deficiencies in Greenlanders. Maybe folate. Small amounts of sugar in small intestine would superficially seem to help with that. Folate deficiency really screws up pregnant women. As a hypothesis for a future research paper, it all kinda adds up, almost too neatly (conspiracy theory like). So their diet is not exactly folate rich, their pregnant women get all messed up, someone gets a mutation where their gut bacteria which produce folate get turbocharged by a couple berries, thus producing more folate in their gut, which optimistically is absorbed by their pregnant women, so women with that mutation have like three times as many living children as folate-deficient women without the mutatuon, it all kinda adds up.

I got google-y for fun and every scientific paper title implies its inuit greenlanders whom have the mutation, not the euro greenlanders, and greenland is about 90% inuit. The picture of the prof looks like he's a euro greenlander looks like Denmark heritage to me but who knows (and it doesn't matter much anyway).

wikipedia says the inuit greenlanders have been chillin on the island for near 5000 years now.

I would imagine due to intermarriage, if the euro greenlanders are outnumbered 10 to 1, that quite a few euro greenlanders have the mutation, but the paper titles all seem to imply inuit greenlanders only.

The wikipedia article implies the archeological inuit greenlander diet was mostly carnivore. That's actually pretty healthy as long as they eat enough organ meats but not too much (particularly liver)

That’s not always how evolution works, especially when you’re talking about characteristics that (as the writer pointed out) were not present or used during evolutionary selection. Adaptations that are selected for can and frequently do have byproduct effects that are not selected for. There are words for these effects, like “vestigial”, “tag-along”, “spandrel”, “byproduct”, “non-adaptive trait”, etc., etc.

> Imagine being able to swap out broccoli for sweets, Ben & Jerry's or some other sugary treat and achieve the same health benefits.

The study finds the genetic variation/gut bacteria metabolizes the sugar directly from the intestines as opposed to being deposited in the blood-stream and triggering insulin to remove it and begin either the metabolic process or storage.

That is a metabolic benefit for sure and as a result could protect from metabolic and chronic diseases. But nothing about that process improves the nutritional value/health benefits of the sugar. Broccoli contains vitamins, minerals, and potentially enzymes (depending on cooking method) which the sugar doesn’t gain.

the more important question is if a mutation presents as a disadvantage for reproduction.

That sentence is saying the diet is millennia old. The diet and genetic variation are also common to other Inuit populations.

(Note: I am an amateur Nutritional Geneticist)

They said:

"The results demonstrate that carriers of the genetic variation have what is known as sucrase-isomaltase deficiency, meaning that they have a peculiar way of metabolizing sugar in the intestine. Simply put, they do not absorb ordinary sugar in the bloodstream the way people without the genetic variation do. Instead, sugar heads directly into their intestine."

Ha! What? SI, the gene that they studied, ONLY exists in the intestine. The inability to break down sucrose leads to microbe imbalance that concerts the sucrose to acetate. They are using the word "sugar" to cover everything from sucrose to any other oligosaccaride. They just do not understand the science enough. If you read the study it is clear.

And in NO way doe sthis mean that eating sugar is healthy for them as the title implies!!!! Look at what happens when you have this deficiency!

https://medlineplus.gov/genetics/condition/congenital-sucras... "After ingestion of sucrose or maltose, an affected child will typically experience stomach cramps, bloating, excess gas production, and diarrhea. These digestive problems can lead to failure to gain weight and grow at the expected rate (failure to thrive) and malnutrition. "

So this is NOT a great mutation. There is no such thing as a universal "great" mutation. These genetic changes are just one change in a probably network of changes in the Inuit. Others would include genes like FADS1 and FADS2 and CPT1A.

(NOTE: I have Saami heritage, who are the Inuit of Finland.)

Next:

"'It is probably due to Greenlanders not having had very much sugar in their diet. For the most part, they have eaten meat and fat from fish, whales, seals and reindeer. A single crowberry may have crept in here and there, but their diet has had minimal sugar content,' "

Here the researchers are correct, this is not only a Greenlander trait, but a common trait in all Inuit, and very low sucrose is common in all Inuit diets. https://pubmed.ncbi.nlm.nih.gov/25452324/

And this absolutely is a fitness example. For people with the common allele, the lack of sucrose in the diet leads to lower levels of acetate and these people would die off leaving the survivors with the less common allele to flourish.

I do have a friend who had a severe gastrointestinal issue and basically went through having his bacteria "reset" for a lack of a better term. It was pretty terrible and he was unable to eat most things before and during, but now is back to a pretty normal diet with some modifications. He was on very aggressive antibiotics followed by months long probiotic treatments.

[1]>This discrepancy between adults and children, may be due to the maturation and growth of the small intestine, increasing the capacity to absorb luminal fluid with increasing age, and to dietary adaptation caused by symptoms in childhood.

They are guessing and they are wrong. Higher levels of acetate are just as bad as lower levels of acetate. You know what also raises acetate levels? The metabolism of Alcohol.

The Inuit need a different diet. They do not "get used to" these sugars.

And why should someone who is lactose intolerant eat lactose? We have been getting around this for years by making yogurt and cheese.

to me, this is like finding any random "coffee is good/bad for you" of which there are thousands that conflict, and saying "Aha! This particular one shaped the course of humanity for the last half a century due to a major conflict of interest and prestigious publication!"

were there just so many fewer studies in the 1960s? was there further collusion and influence with Congress and the FDA? did the sugar trade group fly airplanes and drop food pyramid pamphlets everywhere letting everyone know liberation was coming?

From your article:

> After the review was published, the debate about sugar and heart disease died down, while low-fat diets gained the endorsement of many health authorities, Dr. Glantz said.

so everyone just went along with it?

well, I've seen bad studies get headlines on Buzzfeed and stick in the collective conscious based on the headline alone, so stranger things have happened