Welcome to 2024! New studies from the end of 2023

Hello and welcome back! Below is the content of this week's nutrition newsletter - if you'd like to get these updates directly to your inbox, go ahead and subscribe (see the top of the page). Thanks!

Diet Documentaries & a Twin Study

It wouldn't be a new year without a new diet documentary every nutritionist will get texts and DMs about, right? The new Netflix doco released today features a twin study from Stanford and compares vegan and omnivorous diets. Both the study and an explainer are linked below, and the documentary is out today on Netflix (Youtube trailer linked here). Perhaps unsurprisingly twins assigned to a whole-foods plant based diet saw improved LDL concentration compared to the omnivorous diet as well as some other small improvements in measures of metabolic health. What the Washington Post article reports, as well as the study's own supplemental material, is that those assigned to the completely plant-based diet reported lower satisfaction with the diet nearly across the board. Would this change in satisfaction be different if the plant-based diet became a habit and participants felt more confident in it? The study itself is fascinating and if you have the inclination, I recommend reading the full study in addition to the reporting.

Study on the Great British Bake Off Christmas Ingredients

The Christmas Issue of the British Medical Journal (BMJ) was published and if you missed it, you missed this confection of an article: "Association of health benefits and harms of Christmas dessert ingredients in recipes from The Great British Bake Off: umbrella review of umbrella reviews of meta-analyses of observational studies."

If you don't know, the BMJ features real, yet entertaining, research papers in its Christmas issue and this article is no exception. If you are a nerd (like myself), you will really enjoy this article - I read part of it out loud to my partner (sadly, he was not as appreciative). They categorized all individual ingredients used in Great British Bake Off Christmas Dessert recipes into 17 groups. They then searched for existing umbrella reviews of these ingredients (there were 46) and looked to see their associations with risk of death or disease, sorted into categories from "Convincing" to "Non-Significant." If you need to skip to the end, their conclusion reads: "...if concerns about the limitations of observational nutrition research can be set aside, you can have your cake and eat it too."

How much are you snacking?

Though intermittent fasting has been all the rage for a number of years among a certain set, it seems that many Americans (myself included) get a significant proportion of their daily calories from snacks. A new study specifically examined the proportion and types of foods eaten as snacks by folks according to their HbA1c (a measure of blood sugar over time), but one of the major findings is that *everyone* regardless of blood sugar is eating a lot of their daily calories from snacks, and that these foods tend to be lower in nutrient density.

Protein Absorption

There has been a lot of conversation about protein recommendations recently and how they might be updated based on age, or type of amino acid score, etc. Here, Ally Gallop MS, RD, CSSD and Director of Performance Nutrition at the University of Washington, breaks down a new study that seemingly changes how we think about postprandial protein absorption, particularly from a muscle growth and development perspective.