I just saw this. It’s an excerpt from “Vegan Nutrition Guide” where the author encourages consumption of fat-rich foods and high-fat diets overall. It was written by Virginia Messina, MPH, RD, who runs the popular TheVeganRD.com website:

Don’t hesitate to include other fat-rich foods in your diet, too, if you like them. Low-fat diets are based on an outdated understanding of nutrition that’s been largely discredited. Current recommendations support a wide range of fat intakes for good health, anywhere from 20 to 35 percent of daily calories. (This translates to 22 to 39 grams of fat for every 1,000 calories you eat.) What matters most isn’t how much fat you consume, but rather the type of fat you choose.

There’s something that’s not being said in this. Messina used to advocate low-fat. And, no, low-fat diets have not lost favor, they are not “outdated,” they have not been “discredited.” These words, without any back-up, are a red flag. “Discredit” implies that original research was seriously flawed or biased, enough that publishers retract or unpublish the work. I have not seen retraction in this context. “Outdated” implies that newer science favors higher-fat diets. That’s also not the case. I’ve posted study after study that finds benefit to eating low-fat. Here’s one:

Obesity Energetics: Body Weight Regulation And The Effects Of Diet Composition, Gastroenterology, Online 10 Feb 2017

Our meta-analysis of 32 controlled feeding studies with isocaloric substitution of carbohydrate for fat found that both energy expenditure and fat loss were greater with lower fat diets.

It also said:

These results are in the opposite direction to the predictions of the carbohydrate-insulin model.

The carbohydrate-insulin model predicts that the more carb we eat, the more insulin we will secrete – and since insulin directs fat-storage, the more fat we will accumulate. This study found the opposite. It’s not carbs that make us fat, it’s fat that makes us fat. This is what Dr. McDougall has been saying all along, “The fat you eat is the fat you wear.”

It’s worth noting that the lead author on that study, Kevin Hall PhD, may have gone into it with an expectation that high-fat diets were beneficial. He lists “funding from the Nutrition Science Initiative (NuSI) to investigate the effects of ketogenic diets on human energy expenditure.” Ketogentic diets are low-carb, high-fat diets. NuSI is Gary Taubes’ well-funded initiative that I wrote about here: Gary Taubes Is A Low-Carb Advocate. His Multimillion-Dollar Start-Up, NuSI, Found Low-Carb Diets Don’t Work. NuSI lauds itself by claiming its studies are “more rigorous than all of the nutrition research conducted to date.”

So, something happened in Ginny Messina’s life that made her start advocating dietary fat, and it wasn’t science, as she claims:

Based on the extensive research on the health benefits of different unsaturated fats, it’s very difficult to conclude that low-fat diets would have any particular advantage. … Most of us who used to promote benefits of low-fat eating are headed in a new direction as we follow the science.

Low-fat diets have no advantage? That is patently false.

High-fat diets are especially problematic for people with diabetes. Dietary fat contributes to insulin resistance which leads to higher blood levels of glucose and a need for more insulin. (People with type 1 diabetes can experience fat-related insulin resistance just like people with type 2). When you give people with type 1 diabetes a high-fat meal and a low-fat meal, they need more insulin to cover the high-fat meal, even though both meals contain the same amount of carbohydrate and protein: