Does Yogurt Reduce the Risk of Type 2 Diabetes?
by Christine Craig, MS, RD, CDCES

On March 1st, 2024, the FDA announced they “do not object” to the use of the qualified health claim: “Eating yogurt regularly, at least 2 cups (3 servings) per week, may reduce the risk of type 2 diabetes according to limited scientific evidence.”¹

When I learned of this announcement, my curiosity perked up; my obsession with yogurt started in the late nineties during a microbiology project in which I plated different over-the-counter yogurts and compared the growth.

I was fascinated by the relationship between probiotics and health, and I learned from my research that not all yogurts were created equal. The ADA Standards of Care have recognized the health of the microbiome is essential for preventing and treating diabetes and still, to date, no specific recommendation has been stated regarding inclusion of yogurt. Probiotics have many beneficial effects, including enhancing the immune system, treating diarrhea, lowering cholesterol, and treating IBD and IBS.

But what about yogurt and diabetes prevention? We know there is more to the microbiome health than just yogurt, but are there specific yogurts we can consider recommending? How can we apply these recommendations practically across eating patterns using person-centered care?

What does the FDA consider yogurt?

The term yogurt likely originates from the Turkish term “yogurmak”, which means to thicken, coagulate, or curdle.² Although modern times have updated how it is packaged (including many flavors, stabilizers, and texture enhancements), yogurt originated from 5000-10,000 BC when milk was packed into stomach lining sacks, and the curdling process that resulted, served as a natural preservative.² Today, yogurt is defined by the FDA as a cultured food of one or more basic dairy ingredients, cultured with lactobacillus bulgaricus (l. bulgaricus) and streptococcus thermophilus bulgaricus (s. thermophilus). Probiotic yogurts may contain additional strains of bacteria, such as bifidobacterium lactis or lactobacillus acidophilus but, on the shelf, you can find yogurts with many other probiotic strain additives.

Yogurt, by definition, has a pH of 4.6 or lower and is allowed to be treated after culturing to inactivate viable microorganisms and extend shelf-life.³ However, those treated after culturing must state on the label “does not contain live and active cultures,” and those containing “live and active cultures” must have a minimum of 10⁶ CFU at self-life expectation. Nutritionally, yogurt is a good source of calcium, phosphorus, potassium, Vitamin A, B2, and B12 and has about 8 grams of protein per cup in conventional yogurts.

What is the evidence for diabetes prevention?

Five meta-analyses and additional observation studies were reviewed within the petition to the FDA.⁴ The most recent, 2016 meta-analysis reviewed 22 prospective cohort studies completed within 4 countries of origin.⁵ Eleven of the studies evaluated yogurt and they reported a 14% lower type 2 diabetes risk when including at least 80 grams of yogurt per day (~1/3 cup). They found greater significance and confidence within subpopulations, including women or older (>60) adults. Most studies included conventional yogurts with mixed fat content (some including low-fat while others regular-fat). The amount of added sugar or product type (plain vs. sugar-sweetened yogurt) was not reported. We cannot state a specific type of yogurt that resulted the most significant difference. The FDA, in their statement, called out caution regarding high-sugar yogurt products due to potential concern of contributing to excessive sugar consumption, but no restriction was placed on the allowable claim due to the limited evidence.

The qualified health claim applies to food-based products and not supplements.⁴ We also need to find out if different types of yogurts, including higher protein or plant-based varieties, would have similar outcomes.

Glycemic Benefits of Yogurt in Type 2 Diabetes Management

A 2019 meta-analysis of yogurt’s effects and glycemic outcomes in persons diagnosed with type 2 diabetes reviewed nine randomized control trials.⁶ Yogurt types included mainly probiotic dairy yogurt (L. acidophilus, B. lactis) but also one from goat milk and one from kefir. They reported that probiotic yogurt showed no significant difference in improving HgbA1c, fasting insulin, fasting glucose, and insulin resistance. However, kefir did show a significant difference in A1c and fasting blood glucose reduction. Again, this meta-analysis did not differentiate between low and regular-fat yogurt nor plain and sweetened yogurts. The analysis also did not consider the synergistic effects of other foods to enhance outcomes nor measured microbiome changes. More studies are needed to include larger populations and differentiation of subpopulations that may show benefit.

Can we suggest any yogurt variety?

In 2023, the US yogurt market grew to a 9.38-billion-dollar industry, with growth in yogurt varieties, including higher protein (Greek, Icelandic type, etc.) and plant-based dairy-alternative yogurt products. Higher protein yogurt varieties are generally lower in sugar and almost double the protein at 15-18 grams per serving, they contain about 10-20% of Vitamin D and Calcium. Plant-based yogurts vary in comparable nutrient content, ranging from 11-20 (or more) grams of carbohydrate, 1-8 grams of protein per serving, 2-20% Calcium, 0-10% Vitamin D, and 0-40% B12, and they typically contain live active cultures.⁷ To date, limited studies have been conducted on these products and health outcomes. The variety of yogurt products on the shelf does not match the data evaluated within the FDA petition meta-analysis. Yet, it is essential to support individuals with or at risk of diabetes who choose a plant-based dairy alternative that meets their specific nutrient needs.

The ADA Standards of Care and referenced dietary patterns including the Mediterranean Diet, DASH diet, and general healthful eating patterns recommend including 2-3 servings of dairy per day. These eating patterns also recommend limiting added sugars and high-fat dairy. The meta-analysis results do not provide enough information to suggest a specific type of yogurt, so we can work with individuals to learn their dietary patterns and determine if yogurt may be a good substitute or encouraged current food choice. We can assess an individual’s total fat and sugar intake to determine if yogurt is a significant contributor and can find an appropriate option that supports overall dietary patterns and individual metabolic goals. The microbiome’s health is dynamic, and specific food recommendations will likely be synergistic.

Like a healthy plate, no single food or one-size-fits-all approach is appropriate and as we learn more, many functional food options can be relevant to recommend.

References:

1.    FDA Announces Qualified Health Claim for Yogurt and Reduced Risk of Type 2 Diabetes. Downloaded on March 12, 2024 from https://www.fda.gov/food/cfsan-constituent-updates/fda-announces-qualified-health-claim-yogurt-and-reduced-risk-type-2-diabetes

2.    Hadjimbei E, Botsaris G, Chrysostomou S. Beneficial Effects of Yoghurts and Probiotic Fermented Milks and Their Functional Food Potential. Foods. 2022 Sep 3;11(17):2691. 

3. CFR-Code of Federal Regulations Title 21: Food and Drugs: Part 131 Milk and Cream. Downloaded on March 13^th, 2024. https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=131.200&SearchTerm=yogurt
4. Petition for the Authorization of a Qualified Health Claim for Yogurt and Reduced Risk of Diabetes downloaded on March 12, 2024 from https://www.regulations.gov/document/FDA-2019-P-1594-0001
5. Gijsbers L, Ding EL, Malik VS, de Goede J, Geleijnse JM, Soedamah-Muthu SS. Consumption of dairy foods and diabetes incidence: a dose-response meta-analysis of observational studies. Am J Clin Nutr. 2016 Apr;103(4):1111-24
6. Barengolts E, Smith ED, Reutrakul S, Tonucci L, Anothaisintawee T. The Effect of Probiotic Yogurt on Glycemic Control in Type 2 Diabetes or Obesity: A Meta-Analysis of Nine Randomized Controlled Trials. Nutrients. 2019 Mar 20;11(3):671.
7. Craig WJ, Brothers CJ. Nutritional Content and Health Profile of Non-Dairy Plant-Based Yogurt Alternatives. Nutrients. 2021 Nov 14;13(11):4069.