Cardiac Biomarker Linked with Long-term Paleolithic Diet

A new study indicates that long-term adherence to the Paleolithic diet is associated with increased levels of a key cardiovascular biomarker.

The cross-sectional study, published in the European Journal of Nutrition, compared the diets of 44 participants who had adhered to the Paleolithic diet (often called the Paleo or “caveman” diet) with the diets of 49 participants adhering to a normal diet. Those adhering to the Paleolithic diet were split into strict (n=22) and pseudo (n=22) groups, the latter of which included grains and dairy products in the diet. The researchers looked at dietary intake, colonic health markers, microbiota, and serum levels of the biomarker trimethylamine-N-oxide (TMAO). They assessed the diets with three-day weighted diet records, 48-hour stool analysis for short-chain fatty acids using GC/MS, the microbial environment using 16S rRNA sequencing of the V4 region, and quantified TMAO using LC-MS/MS.

According to the results, intake of resistant starch was lower in both Paleolithic groups, compared to the control group (P<0.05). A PERMANOVA analysis indicated differences in microbiota composition (P<0.05). Most importantly, those adhering to a strict Paleolithic diet had higher serum TMAO compared to the pseudo group, and to controls (P<0.01 for both). This was also inversely associated with whole grain intake (5=-0.34; P<0.01).

“Many Paleolithic diet proponents claim the diet is beneficial to gut health, but this research suggests that when it comes to the production of TMAO in the gut, the Paleolithic diet could be having an adverse impact in terms of heart health,” lead researcher Dr. Angela Genoni, of Edith Cowan University, said in a press release. “We also found that populations of beneficial bacterial species were lower in the Paleolithic groups, associated with the reduced carbohydrate intake, which may have consequences for other chronic diseases over the long term.”

Larger Risks

Dr. Genoni went on to explain the larger concerns for those on these diets, particularly those that exclude whole grains.

“The Paleolithic diet excludes all grains and we know that whole grains are a fantastic source of resistant starch and many other fermentable fibers that are vital to the health of your gut microbiome,” Dr Genoni said. “Because TMAO is produced in the gut, a lack of whole grains might change the populations of bacteria enough to enable higher production of this compound. Additionally, the Paleolithic diet includes greater servings per day of red meat, which provides the precursor compounds to produce TMAO, and Paleolithic followers consumed twice the recommended level of saturated fats, which is cause for concern.”

Paleo diet semi-cilincal study. Oh no, TAMO – 'A variety of fiber components, including whole grain sources may be required to maintain gut and cardiovascular health. https://t.co/1BHifQ4AXU

— Miki Ben-Dor (@bendormiki) July 9, 2019

I can honestly say I told you so; I've been predicting this for years: "People who follow the #Paleo diet have twice the amount of a key blood biomarker linked closely to heart disease" https://t.co/BsfZr6VBy7 Study https://t.co/imKgnEUUV2 #HeartDisease #PaleoDiet #meat #gut pic.twitter.com/fGIYvk8MAS

— Ivor Goodbody (@IvorGoodbody) July 23, 2019

Long-term adherence to the paleo diet is associated with increase in marker (TMAO) for cardiovascular disease: https://t.co/KTBfsb87de

— Daniel Berglind, PhD (@DanielBerglind) July 23, 2019