whole30 diet study

Whole30 Diet Study: Whole30 Rules Have Contradictory Weight Loss Results

Thryve Inside recently conducted an internal study about the changes in a person’s gut biome when they switched from their everyday meal plan to following Whole30 rules. Results found that after five days of going without inflammatory food groups can boost the abundance of stomach bacteria associated with weight loss. However, it does so at the determent of other stomach bacteria. What can you eat on a Whole30 diet, and is this weight loss program for you? Let’s take a closer look at our Whole30 diet study results.


Whole30 Diet Study Methodology

Our Thryve Inside Whole30 diet study was conducted in three phases over a ten-day period. Phase A saw our volunteer consume their standard long-term diet. They followed this protocol for two days.
Whole foods in Whole30 FTW
In Phase B, the participant followed Whole30 rules for five days. We gave this study a little more time to get a real snapshot of how the Whole30 program works.
Medical experts found that your gut bacteria alters to changes in your regular meal plan in approximately three days [1]. Seeing as the Whole30 program is an elimination diet, we needed to wait and see how the gut biome reacted to the omission of inflammatory food groups.
Days eight through ten were Phase C. During Phase C, our volunteer went back to the diet they followed in Phase A.
Every day of this Whole30 diet study, we sampled the gut biome of our participant. Let’s take a look at the differences following Whole30 rules has on the digestive tract, as compared to their normal routine.


What is the Whole30 Program?

whole30 30-day elimination period
Can you go 30 days without some of
your fave foods?
Last decade, U.S. news sources started buzzing about this new 30-day diet plan. Like any standard nutrition plan heralded by nutrition experts, Whole30 promotes eating real food instead of junk food and unhealthy processed foods. However, they take it a bit further by categorizing potential inflammatory food groups. They then abstain from these food sources for 30 days.
Once your month-long inflammatory sabbatical is over, you slowly re-introduce these foods into your normal routine. The point of Whole30 is to indicate potential dietary triggers that may cause discomfort along your digestive tract. That’s why U.S. news sources gave the Whole30 program the trendy nickname of “the elimination diet.


What’s Not Allowed on Whole30 Elimination Diet?

The trickiest part of being on an elimination diet…is being on an elimination diet! You need to get rid of many staples that are part of your regular routine. Let’s take a quick look at the inflammatory foods groups that our volunteer forwent during our Whole30 diet study.


Added Sugars and Artificial Sweeteners

If you’re joining the Whole30 program for weight loss, then you are going to want to avoid artificial sweeteners and any added sugars at all costs. Excess sugar not only stores itself in fat tissues but clog up your liver, as well [2]. If you need help fighting sugar cravings, check out our article on performing a sugar detox.


How Much Fruit Can You Eat On Whole30?

During a Whole30 diet, you can still consume fruit. Organic fruits are whole foods that contain simple processed sugars that promote higher energy levels.
According to the official Whole30 website, you can have as much organic fruit as you want but recommend,

“Our meal template recommends around two servings of fruit per day, eaten with your meals (and not on their own as “dessert” or a snack). However, that’s just a starting point, not a hard and fast mandate. We’re really not concerned with the amount of sugar in whole foods, in the context of a Whole30 diet [3].”

Whole30 (R)
Don’t get this recommendation confused with bottles of fruit juice. Many of these contain added sugars. If you are going to drink juice, make sure to follow the guidelines of our juice cleanse diet study.


Alcohol and Tobacco

foods in elimination diet
Let the sun set on drinking
Smoking isn’t conducive to a healthy lifestyle, nor is it compliant with Whole30 rules. While there may be some benefits to drinking alcohol in moderation, it also breaks the rules of a Whole30 diet.
Sure, red wine has prebiotics, but none during the month-long diet plan. Also, no cooking with wine either. However, you can use red wine vinegar and apple cider vinegar. Drinking kombucha is fair game, too. Just make sure that the kombucha doesn’t have any added sugars.


Whole Grains

The primary reason whole grains are not compliant is that many of these food sources contain gluten. Gluten is one of the most prominent allergens in food [4]. It triggers our body to release zonulin, an enzyme that regulates your gut barrier [5]. That’s why an elimination diet may help fight Leaky Gut Syndrome.
With that said, Whole30 rules also say not to eat gluten-free grains. We can’t find an explanation on their behalf as to why they are omitted. While it seems senseless, our volunteer complied with the Whole30 diet during Phase B.



whole30 diet study
Beans, beans, good for the heart;
but not Whole30
Legumes are essentially any member of the bean family. Therefore, people who follow a Whole30 diet can’t eat any peas, chickpeas, or black beans.
The reason legumes aren’t Whole30-approved is because they contain lectins. Lectins are known as anti-nutrients [6]. They bind to essential nutrients that we get from other food sources. In turn, lectins can promote inflammation, deplete energy levels, and digestive issues.
Many people who follow Whole30 rely on animal proteins to make up for the lack of legumes and whole grains. That makes following a plant-based diet on Whole30 a bit difficult. However, integrate some of the methods we discuss in our article on being a paleo vegan. That might make following Whole30 rules easier.


Peanut Butter

Our test subject was really sad to find out that peanuts were members of the legume family. However, you can still get the same creamy deliciousness from other nut butters. Nut butters commonly used in this popular diet program include almond, macadamia, and cashew.




Dairy is also on the list of foods you can’t eat during a Whole30 diet. That’s because 60% of adults can’t digest lactose [7]. The human body isn’t designed to drink another mammal’s milk far into adulthood. As a result, it causes inflammation in the system of many.
If you need creamer in coffee, you must opt for nut milks. Choose coconut, cashew, or almond milk. Do not consume oat or rice milk, as they are grains. Also, don’t drink soy milk. As healthy as soy can be, it’s also a member of the legume family. Man, Papa Legume gets around!


Other Foods

For time purposes, we’re going to acknowledge here that the Whole30 doesn’t allow processed foods like deli meats, food additives, baked goods, or junk food.


Whole30 Diet Study Results

As you can see, the Elimination Diet is no joke! Did the potential weight loss benefits of Whole30 happen for our volunteer? Let’s take a look at the results of our Whole30 diet study.


Benefits of Whole30 Diet

Some conflicting reports lead us to believe the Whole30 diet is suitable for a healthy lifestyle. However, following Whole30 guidelines might not make it to the top of the list of best diets. Here are the benefits of Whole30 supported by our study.


Improves Colon Health

whole30 diet weight loss
Whole30 promotes more Blautia in the gut biome
Of all the data we compiled during our Whole30 diet study, one benefit stood out from the rest. By the end of the four days of consistently following Whole30 rules, the subject saw increased levels of the stomach bacteria, Blautia. Research on colorectal health notes that low levels are Blautia is associated with colorectal cancer [8].


Supports Liver Function

We put our livers through a lot. This organ is expected to detoxify all of the pesticides in our food, pollution in the air, and toxins on our cosmetics. So, it’s essential there is an adequate balance in gut bacteria to ensure your liver doesn’t endure any excess stress. Blautia is one of those stomach bacteria you want present.
An analysis of the gut-liver-axis noted,

“The sequencing of 16S bacterial RNA showed in the stool of hepatocellular carcinoma (HCC )patients increased abundance of BacteroidesRuminococcusEnterococcusPhascolarctobacterium, and Oscillospira and decreased abundance of Bifidobacteria and Blautia as compared with liver cirrhosis without HCC. In particular, the deficiency of anti-inflammatory bacteria such as Bifidobacteria or Blautia can enhance intestinal and liver inflammation and cause the progression of hepatocarcinogenesis [9].”

Med Sci (Basel)
While Blautia levels peaked on days four and five of the Whole30 protocol, they plummeted the day the test subject returned to their regular diet. At the end of Phase C, the levels were slightly higher than during Phase A. These findings suggest following Whole30 rules for the long-term may keep Blautia levels elevated.


Helps with Weight Loss

Another significant result of switching to the Whole30 program saw a 250% increase in Bacteroides vulgatus. This stomach bacteria is essential in fighting off obesity. Research shows that Bacteroides vulgatus creates two short-chain fatty acids that are pivotal for a healthy metabolism, and ultimately, weight loss [10].
Fight hunger with Whole30
One of these metabolites is propionate. Research shows that propionate causes the body to produce more peptide YY [11].
Peptide YY is a protein that helps with gut motility. It also boosts water and electrolyte absorption in the large intestine. Most notably, for those looking for weight loss benefits of Whole30, peptide YY helps curb our appetite [12].


The other short-chain fatty acid that is essential for a healthy metabolism is acetate. This short-chain fatty acid plays many roles throughout the digestive system and immune system. Like propionate, it can also regulate appetite. However, there are even more weight loss benefits to acetate.
One meta-analysis of this metabolite stated that acetate,

“May improve the obese insulin resistant state through various effects in peripheral tissues that collectively improve body weight control and insulin sensitivity [13].”

Therefore, following a Whole30 program can be very beneficial for someone who has diabetes. Combined with the heart-health benefits of acetate, the benefits of a Whole30 diet seem to be plentiful!


Potential Negative Impact of Whole30

While there were seemingly a lot of benefits of Whole30, they might not be as plentiful as we originally thought. Healthy habits curated by following the Whole30 program saw a rise of many gut bacteria. However, it saw a decline in some, as well. Let’s take a look at some potential cons of an elimination diet.


Has Little Impact On Gut Diversity

Changing up the plate didn’t
change up bacteria
The last significant result from our Whole30 diet study is that following the Whole30 program seemed to do little for overall gut bacteria diversity. While some levels of beneficial stomach bacteria increased, it seemed to do as the detriment of other beneficial bacteria.
By following Whole30 rules, our test subject saw a rapid decrease in Bifidobacterium. This commensal bacteria is essential for vitamin production and immune system support [14].
Unfortunately, our test subject saw a 62.5% decrease in Bifidobacterium while following a Whole30 diet. Furthermore, these levels stayed low when the test subject returned to their normal routine in Phase C.


Boosts Bacteria Associated with Obesity

Sure, Whole30 rules saw an increase in Bacteroides vulgatus. However, the bump in this bacteria seemed to coincide with the rise of Faecalibacterium. This intestinal flora is heavily associated with inflammation, type 2 diabetes, and obesity [15].
Scarily enough, following Whole30 rules saw a 75% increase of Facelbacterium in our test subject that followed them through Phase C.


Can You Lose Weight on Whole30?

Seeing as we didn’t follow a 30-day elimination period, we can’t say whether Whole30 can help you lose weight or not. We can say that there is no harm in eating real food and whole foods and kicking processed foods and junk food to the cub.
gut bacteria and weight gain
Jury is still out on
Whole30 and weight loss
We did take the weight of our test subject during the study. They did lose more weight during the days they were following Whole30 guidelines when compared to their normal routine. At the peak of Whole30, they lost just over two pounds. While that’s impressive over a couple of days, we don’t know the long-term weight loss benefits of Whole30.
Based on the data from our Whole30 diet study, we believe a person would get better nutrition than a standard diet. However, they might not lose as much weight as they’d hope. We believe this because the levels of
Bacteroides vulgatus and Faecalibacterium might cancel each other out over the 30-day experiment.
If you follow a Whole30 diet, we can help you attain optimal stomach bacteria biodiversity. Allow us to test your gut biome so we can recommend custom probiotics. That way, you can get the nutritional benefits of Whole30 and a wide-range of stomach bacteria essential for weight loss.

Click Here To View Resources



[1] Feltman, Rachel. “The Gut’s Microbiome Changes Rapidly with Diet.” Scientific American, 14 Dec. 2013, www.scientificamerican.com/article/the-guts-microbiome-changes-diet/.
[2] Ma, J., Karlsen, M. C., Chung, M., Jacques, P. F., Saltzman, E., Smith, C. E., Fox, C. S., & McKeown, N. M. (2016). Potential link between excess added sugar intake and ectopic fat: a systematic review of randomized controlled trials. Nutrition reviews, 74(1), 18–32. https://doi.org/10.1093/nutrit/nuv047.
[3] “Whole30 101: Rules vs Recommendations.” The Whole30® Program, 25 Mar. 2020, whole30.com/rules-recommendations/.
[4] Leonard, M. M., & Vasagar, B. (2014). US perspective on gluten-related diseases. Clinical and experimental gastroenterology, 7, 25–37. https://doi.org/10.2147/CEG.S54567.
[5] Fasano A. (2012). Zonulin, regulation of tight junctions, and autoimmune diseases. Annals of the New York Academy of Sciences, 1258(1), 25–33. https://doi.org/10.1111/j.1749-6632.2012.06538.x.
[6] Roos, Nanna, et al. “Screening for Anti-Nutritional Compounds in Complementary Foods and Food Aid Products for Infants and Young Children.” Maternal & Child Nutrition, U.S. National Library of Medicine, Jan. 2013, www.ncbi.nlm.nih.gov/pubmed/23167584.
[7] Itan, Yuval, et al. “The Origins of Lactase Persistence in Europe.” PLOS Computational Biology, Public Library of Science, 28 Aug. 2009, journals.plos.org/ploscompbiol/article?id=10.1371%2Fjournal.pcbi.1000491.
[8] Zou, S., Fang, L., & Lee, M. H. (2018). Dysbiosis of gut microbiota in promoting the development of colorectal cancer. Gastroenterology report, 6(1), 1–12. https://doi.org/10.1093/gastro/gox031.
[9] Konturek, P. C., Harsch, I. A., Konturek, K., Schink, M., Konturek, T., Neurath, M. F., & Zopf, Y. (2018). Gut⁻Liver Axis: How Do Gut Bacteria Influence the Liver?. Medical sciences (Basel, Switzerland), 6(3), 79. https://doi.org/10.3390/medsci6030079.
[10] Chakraborti C. K. (2015). New-found link between microbiota and obesity. World journal of gastrointestinal pathophysiology, 6(4), 110–119. https://doi.org/10.4291/wjgp.v6.i4.110.
[11] Chambers, Edward S, et al. “Effects of Targeted Delivery of Propionate to the Human Colon on Appetite Regulation, Body Weight Maintenance and Adiposity in Overweight Adults.” Gut, BMJ Publishing Group, 1 Nov. 2015, gut.bmj.com/content/64/11/1744.
[12] Karra, E., Chandarana, K., & Batterham, R. L. (2009). The role of peptide YY in appetite regulation and obesity. The Journal of physiology, 587(1), 19–25. https://doi.org/10.1113/jphysiol.2008.164269.
[13] Hernández, M., Canfora, E. E., Jocken, J., & Blaak, E. E. (2019). The Short-Chain Fatty Acid Acetate in Body Weight Control and Insulin Sensitivity. Nutrients, 11(8), 1943. https://doi.org/10.3390/nu11081943.
[14] O’Callaghan, A., & van Sinderen, D. (2016). Bifidobacteria and Their Role as Members of the Human Gut Microbiota. Frontiers in microbiology, 7, 925. https://doi.org/10.3389/fmicb.2016.00925 .

You May Also Enjoy These Articles:

vitamin metabolism
Cofactor and Vitamin Metabolism

Our body is like one big science experiment. Chemical reactions influence everything from physical movement to emotional well-being to your gut health. The catalysts for

glycan metabolism
Glycan Metabolism: Analyzing KEGG Pathways

Glycan metabolism is necessary for protein synthesis, connective tissue repairs, and fighting off infections.   The microbiome opens the pathway to understanding how the body

Share this post

Share on facebook
Share on google
Share on twitter
Share on linkedin
Share on pinterest
Share on print
Share on email

© 2020 Quantbiome, Inc. (dba Thryve) ​​​

1475 Veterans Blvd. Redwood City, CA 94063​