Tanya M Halliday was in Chicago covering the Nutrition 2024 Congress in July 2024. She attended the conference on yogurt consumption and reduced risk of type 2 diabetes and shared her analysis with us. She deciphered for us the science and process behind a qualified health claim.

As Registered Dietitians (RDs), staying up to date with both nutrition science and food label claims allows us to provide both evidence-based and actional nutrition-related advice to clients. In March the U.S. Food and Drug Administration (FDA) approved a Qualified Health Claim regarding yogurt consumption and reduced risk of Type 2 Diabetes. To better understand how FDA came to authorize this first claim related to yogurt, this post will: 1. Explain what a Qualified Health Claim is; and 2. Summarize the FDAs process for evaluating the science behind the health claim.

What is a “Qualified Health Claim”?

In the United States, “health claims” that can be used on food and dietary supplemental labels are defined by statute and/or FDA regulations and have two levels. [1].

1. Authorized Health Claims, in which there must be “significant scientific agreement (SSA)…that provides a high level of confidence in the validity of the substance/disease relationship”. [2] To date only 12 qualified health claims have been approved [3].
2. Qualified Health Claims, which are “supported by scientific evidence, but do not meet the more rigorous ‘significant scientific agreement’ standard required for an authorized health claim. [4] Essentially, while there is scientific support for these claims, the wording required ensures the potential health benefit is not overstated. A full list of qualified health claims can be found online.

Specifically, the FDA does not “approve” qualified health claims. Instead, it will issue a “letter of enforcement” which provides the agency’s evaluation of the scientific evidence relevant to the proposed qualified health claim and (if moving forward) will provide specific language for which the FDA will provide enforcement discretion.

Specifics for the yogurt and Type 2 Diabetes Qualified Health Claim

The qualified health claim for yogurt was initiated via a petition submitted by Danone North America, which the FDA responded to on March 1, 2024. All 51 pages of it can be read here. Ultimately the outcome was that the FDA “intends to consider exercising its enforcement discretion for the following qualified health claims:

1. “Eating yogurt regularly, at least 2 cups (3 servings) per week, may reduce the risk of type 2 diabetes. FDA has concluded that there is limited information supporting this claim”
2. “Eating yogurt regularly, at least 2 cups (3 servings) per week, may reduce the risk of type 2 diabetes according to limited scientific evidence”

Fat and Added Sugar Content Specifics: Given that there are a variety of yogurts available for purchase with varying fat and added sugar content there have been concerns voiced about yogurts high in these components. However, as most of studies did not differentiate between specific types of yogurts and the credible scientific evidence still found a statistically significant reduction in type 2 diabetes risk irrespective of fat or sugar content, this claim does not require use only on products with specific fat or added sugar levels.

Disqualifying Nutrient Levels: Under the FDAs general requirement for health claims, claims are not allowed on any product that exceeds “disqualifying nutrient levels” for total fat, saturated fat, cholesterol, or sodium. [5] Specific disqualifying health levels, such as 13g of fat per RACC (reference amount customarily consumed) and per label serving size, are generally not reached for the majority of yogurt products, and thus unlikely to be a concern for consumers. There is not currently a disqualifying nutrient level for added sugar content of food. However, the FDA did note in their response to petition that “we are concerned that the use of a qualified health claim on yogurts that contain a significant amount of added sugars could contribute empty calories to the diet” and ultimately that because “…some yogurts on the market are high in added sugars, FDA encourages careful consideration of whether to use the claim on products that could contribute significant amounts of added sugars to the diet”.

The evidence for yogurt consumption and Type 2 Diabetes Qualified Health Claim

In the petition submitted by Danone North America, 117 publications were cited. The FDA identified additional literature (mostly published after submission of the petition) to consider.

Of these, the FDA included only 28 observational studies from which scientific conclusions could be drawn! So why did they “toss out” so many studies? Multiple reasons!

First, literature considered “background materials”, including review articles, meta-analyses, reports from federal agencies, etc. were not included as they “do not contain sufficient information on the individual studies reviewed, and therefore, FDA could not draw any scientific conclusions regarding the substance-disease relationship from these sources”.

Second, the 20 controlled intervention studies which examined the effect of yogurt on type 2 diabetes surrogate endpoints were not considered because they were determined to not be sufficiently controlled. For instance, conventional yogurt was compared to a modified yogurt (such as supplemented with brewer’s yeast), but not to a non-yogurt placebo.

Third, for the observational studies, several were excluded due to a variety of reasons. While not listing all of the reasons (you can read those all in the 51 page response from the FDA though!) for example, these include: studies not exclude participants with type 2 diabetes at baseline; studies not adjust the analysis for relevant cofounders (such as physical activity); and failed to evaluate the independent effect of yogurt.

Of the 28 observational studies, over 860,000 participants were included across 27 cohorts and 10 countries. All but one study estimated yogurt intake using food frequency questionnaires (FFQ). The one remaining study by O’Connor et al, 2014 [6] used a 7-day food recall. Studies included could look at the association between yogurt intake and incidence of type 2 diabetes or surrogate end points (such as prediabetes), as well as the change in yogurt intake and incidence of diabetes or surrogate end points. Importantly, the FDA classifies the literature based on methodological quality. 9 were considered to be of high methodological quality and a significant association was observed for both incidence of type 2 diabetes and the surrogate end point of fasting glucose. 19 were considered to be of moderate methodological quality and findings were mixed and inconsistent. For instance, Liang et al 2017 [7] found that yogurt intake was statistically associated with a reduced risk of type 2 diabetes among women, but not men.

Summary and implications for dietary advice

Overall, the FDA concluded that while there is credible evidence supporting a relationship between regular yogurt consumption and reduced risk of type 2 diabetes, the evidence is limited. Specifically, no randomized controlled trials were included and there were inconsistent findings. That being said, it is unlikely that there will ever be randomized controlled trials conducted to determine the influence of yogurt consumption on diabetes risk. This is because diabetes takes years to develop and it would not be feasible to randomize people to different yogurt intake levels for most of their life.

When working with clients, this new qualified health claim can be utilized to support the recommendations you are already likely to give to your clients. Yogurt can be a versatile and nutritious addition or substitution to meals and snacks that provide protein, probiotics, and essential nutrients. Furthermore, the addition of yogurt to the diet can aid in clients meeting the Healthy Eating Index’s dairy component targets as part of an overall healthful diet!

Bon appetit!

Tanya Halliday, PhD, RD is an Assistant Professor in the Department of Health & Kinesiology at the University of Utah. Her research focuses on how exercise of differing modalities influences appetite regulation and energy intake; development of novel interventions for weight loss maintenance, and examination of lifestyle interventions and glycemic-related outcomes. Dr. Halliday completed her Bachelor’s degree in Dietetics from the University of Wyoming (2010), and her Dietetic Internship at the University of Houston (2011). After receiving her RD credential, she went to Virginia Tech for her PhD in Clinical Physiology, and Metabolism. She graduated in 2016, receiving the College of Agriculture and Life Sciences Outstanding Doctoral Student Award, before moving to Denver for postdoctoral training at the University of Colorado’s Anschutz Medical Campus from 2016-2018. Dr. Halliday has been at the University of Utah since 2018 where her research has been funded by the NIH and multiple internal pilot grants. In addition to her research program, Tanya serves as a member of the Academy of Nutrition and Dietetics’ Weight Management Expert Panel. She is passionate about the career development of her lab member’s and in 2022 received the College of Health’s Distinguished Mentor Award.

Type 2 Diabetes is a growing global health crisis, demanding comprehensive strategies to combat its rise. As highlighted during the symposium ‘Yogurt and Reduced Risk of Type 2 Diabetes: Exploring the New FDA Qualified Health Claim and Potential Implications for Improving Public Health’ at the ASN Nutrition 2024, incorporating nutrition expertise and food-based approaches, such as yogurt with its unique nutrient profile, is crucial in addressing diabetes risk. In this interview, Dr Christopher Cifelli, PhD discusses the recent FDA-qualified health claim on yogurt’s role in reducing type 2 diabetes risk and its broader implications for public health and nutrition policies.

Key messages:

• On March 1st, the FDA announced a qualified health claim outlining that regular yogurt consumption (at least 2 cups or 3 servings per week) may reduce the risk of type 2 diabetes, according to limited scientific evidence.
• The body of evidence, which analyzed data from over 800,000 individuals, supports that yogurt consumption is associated with better health outcomes, particularly in reducing the risk of type 2 diabetes.
• Yogurt is a nutrient-dense food that provides essential nutrients and fits well within the three healthy dietary patterns recommended by the Dietary Guidelines for Americans.
• The unique food matrix of yogurt, including its nutrient content and fermentation products, may contribute to its protective effects on cardiometabolic health, independent of its fat content. Study results align with broader research on yogurt and overall health benefits.

Can you introduce yourself and let us know about your work?

I am Senior Vice President of Nutrition Research at the National Dairy Council, which represents the nearly 30,000 dairy farmers across the United States through our checkoff organization.

How would you describe the burden that type 2 diabetes represents?

Type 2 diabetes (T2D) is a significant health concern in the United States, with 38.4 million people affected, representing 11.6% of the population. Additionally, 8.7 million people are undiagnosed, and 97.6 million adults have prediabetes, increasing their risk of developing T2D. Over the past two decades, the number of adults diagnosed with diabetes has more than doubled, making it the eighth leading cause of death. The financial impact is substantial, with medical costs and lost wages for those with diagnosed diabetes totaling $413 billion annually. Medical costs for people with diabetes are more than twice as high as those without the condition.

Healthy lifestyle choices are crucial in reducing the risk of T2D and mitigating public health costs. Maintaining a healthy weight, engaging in regular physical activity, and following a balanced diet are key strategies for T2D prevention, treatment, and management. Weight loss helps lower the risk of T2D and other chronic diseases, regular exercise aids in blood sugar management and reduces the risk of heart disease, and a nutritious diet is essential for overall health. For more detailed information, resources such as the International Diabetes Federation’s data portal and the USDA’s Dietary Guidelines for Americans 2020-2025 can provide valuable insights.

How does yogurt consumption compare with other dairy products in terms of its impact on the risk of type 2 diabetes?

All dairy products contain essential nutrients and are generally healthy. Milk’s unique nutrient package offers a range of essential vitamins and minerals, including calcium, iodine, riboflavin (B2), vitamin B12, protein, potassium, vitamin D, phosphorus, vitamin A, niacin (B3), pantothenic acid (B5), selenium, and zinc. These nutrients make dairy foods a powerful contributor to a healthy diet, providing essential components that support various bodily functions and overall well-being.

However, when it comes to type 2 diabetes, regular yogurt consumption may reduce the risk. This association is observed across numerous prospective cohort studies in various populations both in the US and globally. In contrast, milk and cheese do not exhibit the same level of consistency in reducing type 2 diabetes risk. Yogurt stands out as the most consistently linked dairy food associated with a reduced risk of type 2 diabetes.

What evidence supports the role of yogurt in reducing the risk of type 2 diabetes in different demographic groups such as children, adults, and the elderly?

Most of the research on yogurt’s role in reducing the risk of type 2 diabetes has been conducted in adults, primarily through observational studies. Several meta-analyses have also been performed. The FDA, in their review of the evidence, cited 28 studies, with the majority showing a reduction in type 2 diabetes risk. This body of research spans decades, and demonstrates yogurt’s role in reducing the risk.

Four meta-analyses have consistently associated yogurt intake with a reduced risk of Type 2 Diabetes (T2D). Studies by Tong et al. (2011), Gao et al. (2013), Chen et al. (2014), and Gijsbers et al. (2016) demonstrated relative risk reductions ranging from 0.85 to 0.94 across various cohorts, highlighting yogurt’s beneficial impact. The FDA’s rigorous review process, spanning from 2019 to 2024, culminated in a qualified health claim linking yogurt consumption to a reduced risk of T2D, according to limited scientific evidence. This work, led by Danone, involved a thorough analysis of over 100 studies, and ultimately drew conclusions from 28 studies with over 860,000 subjects from 27 cohorts in 10 countries, consistently showing yogurt’s positive effect. Additionally, research from PREDIMED and other large prospective cohorts in the U.S. and globally supported these findings, demonstrating yogurt’s significant association with reduced T2D risk.

The scientific literature underscores yogurt’s unique role compared to other dairy products in lowering T2D risk. Various studies across different demographic groups, including the general adult population, postmenopausal women, and elderly populations, support the link between regular yogurt consumption and a decreased risk of type 2 diabetes. The Joslin Diabetes Center’s 2018 clinical nutrition guidelines recommend including yogurt as part of a healthy dietary pattern for those with or at risk for T2D, regardless of fat content. Moreover, emerging evidence suggests that yogurt may have anti-inflammatory effects, contributing to the prevention of noncommunicable diseases like diabetes. This extensive body of research highlights the importance of yogurt as a valuable component of a diabetes-prevention diet.

What biological mechanisms have been proposed to explain the inverse relationship between yogurt consumption and the risk of type 2 diabetes?

While still not fully understood, there are several potential mechanisms by which yogurt consumption may help reduce the risk of type 2 diabetes. Firstly, yogurt itself can help reduce appetite, as dairy proteins have been shown to lower appetite when part of a healthy diet. Secondly, the unique fats produced by the starter cultures in yogurt have been shown to impact liver function, improve metabolism, and reduce insulin resistance. Additionally, studies have indicated that yogurt can help maintain gut barrier function and lower inflammation. These are three key mechanisms through which yogurt may help reduce diabetes risk.

Yogurt’s profile also supports general health. Its essential nutrients such as protein, calcium, and other minerals make it unique when considering nutritional adequacy. Additionally, the bacteria and bacterial enzymes in yogurt can help support digestive health, while fermentation products like short-chain fatty acids, bioactive peptides, and B vitamins contribute to its positive effects. Yogurt also offers other benefits like lower pH and increased nutrient bioavailability, supporting overall health.

Iodine is a trace element, which the body needs in very small amounts to stay healthy. What are its functions and where to find it?

What is iodine?

Iodine is a mineral, a trace element, mostly stored in our thyroid gland, which releases several thyroid hormones like thyroxine (T4) and triiodothyronine (T3). Iodine is essential for these hormones as it makes up 65 and 59% of the weight of the molecules respectively. These hormones are regulated by Thyroid-Stimulating hormone (TSH) whose secretion increases the uptake of iodine in the thyroid. These hormones regulate biochemical reactions including protein synthesis, enzymatic activities and metabolic activities such as body temperature regulation and maintenance of energy levels. In a deficiency state, TSH remains elevated and leads to goitre: an enlargement of the thyroid gland. In pregnancy, even a mild case of iodine deficiency is serious as it can cause problems in the child’s development and cognition, and it is considered one of the easiest preventable deficiencies leading to neurodevelopmental disorders.

Dietary recommendations

• For teenagers and adults, it is recommended to consume 150µg per day of iodine.
• The recommendation climbs to 220µg/day during pregnancy and 290µg during lactation.
• Recommendations are much higher in the first year of life at 130µg than during childhood (90µg). This is because in early developmental stages, iodine deficiency can lead to stunted growth and neurodevelopmental deficits.
• During the 9-13-year-old age group, the recommendation goes back up to 120µg.

Although it is difficult to consume too much iodine in a healthy and balanced diet, it is suggested to not consume more than 600µg per day in healthy adults.

Sources of iodine

Iodine can be found mostly in seaweed, fish and seafood, eggs, and dairy.

Many countries have fortified table salt with iodine as the salt form of iodine is the main form absorbed in the body. It is estimated that 88% of households have iodine-fortified salt. However, countries also have efforts to decrease salt consumption therefore dairy is becoming a more interesting source of iodine.

When to pay extra attention?

To some people, it might be hard to get enough iodine from their diets, as their needs are increased, or their food sources are limited.

For vegans, vegetarians and those who exclude fish and algae from their diets, it might be difficult to get enough iodine from the diet. They need to pay extra attention to their iodine intake. It is particularly concerning during pregnancy and childhood (up to the age of 3 years old).

Iodine in dairy

Iodine content in milk varies widely depending on the diet of the animal. There can even be seasonal variability in iodine concentrations, for example, cattle grazing on grass in the summer will produce milk with less iodine than cattle fed with cattle feed containing iodine in winter. All of this makes milks’ iodine concentrations vary from 33 to 534 µg/L. This means dairy can represent 13-64% of the recommended daily intake of iodine.

In UK, milk has on average 427µg/L and dairy products contribute to 51% of iodine intake in children and 34% in adults.

Even though the concentration of iodine in dairy milk varies widely it is still on average 10 times higher than in plant-based alternatives. Thus, dairy remains a good source of this nutrient for health, especially in places that don’t have easy access to seafood or iodised salts.

According to the national diet and nutrition survey in the UK, people who consume yogurt regularly were more likely to meet the nutrient recommendations for key vitamins and minerals including iodine compared to those who didn’t eat yogurt regularly.

It is recommended to consume 2-3 portions of dairy per day, yogurt is a nutrient-rich way of getting iodine.