In this episode, we discuss:
- The background of dairy consumption by humans
- A variety of research studies that show that dairy products, and full-fat fermented dairy products in particular, have benefits for cardiometabolic function and several other markers of health
- The mechanisms behind the benefits of full-fat dairy
- The myth that dairy foods contribute to osteoporosis by “acidifying” our bodies
- How to know if you’re intolerant to lactose or the proteins in dairy and how to address that in your diet
- “Milk signalling in the pathogenesis of type 2 diabetes” by Bodo C. Melnik
- “Trans-Palmitoleic Acid, Metabolic Risk Factors, and New-Onset Diabetes in U.S. Adults” by Dariush Mozaffarian, Haiming Cao, Irena B. King, Rozenn N. Lemaitre, Xiaoling Song, David S. Siscovick, and Gökhan S. Hotamisligil
- “Biomarkers of milk fat and the risk of myocardial infarction in men and women: a prospective, matched case-control study” by Eva Warensjö, Jan-Håkan Jansson, Tommy Cederholm, Kurt Boman, Mats Eliasson, Göran Hallmans, Ingegerd Johansson, and Per Sjögren
- “Dairy consumption and patterns of mortality of Australian adults” by M. Bonthuis, M. C. B. Hughes, T. I. Ibiebele, A. C. Green, and J. C. van der Pols
- “Milk drinking, ischaemic heart disease and ischaemic stroke II. Evidence from cohort studies” by P. C. Elwood, J. E. Pickering, J. Hughes, A. M. Fehily, and A. R. Ness
- “Comprehensive Review of the Impact of Dairy Foods and Dairy Fat on Cardiometabolic Risk” by Jean-Philippe Drouin-Chartier, Julie Anne Côté, Marie-Ève Labonté, Didier Brassard, Maude Tessier-Grenier, Sophie Desroches, Patrick Couture, and Benoît Lamarche
- “The relationship between high-fat dairy consumption and obesity, cardiovascular, and metabolic disease” by Mario Kratz, Ton Baars, and Stephan Guyenet
- “Effects of Full-Fat and Fermented Dairy Products on Cardiometabolic Disease: Food Is More Than the Sum of Its Parts” by Arne Astrup, Nina Rica Wium Geiker, and Faidon Magkos
- “Impact of low-fat and full-fat dairy foods on fasting lipid profile and blood pressure: exploratory endpoints of a randomized controlled trial” by Kelsey A. Schmidt, Gail Cromer, Maggie S. Burhans, Jessica N. Kuzma, Derek K. Hagman, Imashi Fernando, Merideth Murray, Kristina M. Utzschneider, Sarah Holte, Jana Kraft, and Mario Kratz
- “Oral butyrate for mildly to moderately active Crohn’s disease” by A. Di Sabatino, R. Morera, R. Ciccocioppo, P. Cazzola, S. Gotti, F. P. Tinozzi, S. Tinozzi, and G. R. Corazza
- “Effects of Ruminant trans Fatty Acids on Cardiovascular Disease and Cancer: A Comprehensive Review of Epidemiological, Clinical, and Mechanistic Studies” by Sarah K. Gebauer, Jean-Michel Chardigny, Marianne Uhre Jakobsen, Benoît Lamarche, Adam L. Lock, Spencer D. Proctor, and David J. Baer
- “Milk and acid-base balance: proposed hypothesis versus scientific evidence” by Tanis R. Fenton and Andrew W. Lyon
- “Carbonated beverages and urinary calcium excretion” by Robert P. Heaney and Karen Rafferty
- “Phosphate decreases urine calcium and increases calcium balance: A meta-analysis of the osteoporosis acid-ash diet hypothesis” by Tanis R. Fenton, Andrew W. Lyon, Michael Eliasziw, Suzanne C. Tough, and David A. Hanley
- “A dairy and fruit dietary pattern is associated with a reduced likelihood of osteoporosis in Korean postmenopausal women” by Sangah Shin and Hyojee Joung
- “The Association Between Osteoporosis and Hypertension: The Role of A Low Dairy Intake” by Massimo Varenna, M. Manara, L. Galli, L. Binelli, F. Zucchi, and L. Sinigaglia
- “Dairy Products, Dietary Calcium and Bone Health: Possibility of Prevention of Osteoporosis in Women: The Polish Experience” by Lidia Wadolowska, Kamila Sobas, Justyna W. Szczepanska, Malgorzata A. Slowinska, Magdalena Czlapka-Matyasik, and Ewa Niedzwiedzka
- Cyrex Labs Array 4
- Vibrant Wellness Dairy Zoomer
- Articles by Chris:
Hey, everybody, Chris Kresser here. Welcome to another episode of Revolution Health Radio. One of the most common questions I’ve received over the years is what role dairy products can play in a nutrient-dense, whole foods diet. On one end of the spectrum, you have folks who believe that we shouldn’t be eating dairy products at all. These are people in the Paleo nutrition community and in many alternative, integrative, or Functional Medicine communities. They argue that dairy products are inflammatory and linked with lots of different diseases and that we shouldn’t be eating them because human beings haven’t eaten dairy for very long. On the other end of the spectrum, you have the conventional medical view, which is that dairy products are health-promoting and should be included in the diet when well-tolerated. So in this episode, I’m going to explore what the scientific evidence says about this claim and share a little bit about my clinical experience. Ready? Let’s dive in.
No matter where you personally stand on [the] question of dairy products, there’s no doubt that it’s a contentious issue in the nutrition community. As I mentioned in the [introduction], on one end of the spectrum, you have folks, for example, in the Paleo nutrition community, represented initially by Loren Cordain, who claimed that dairy is not fit for human consumption for two reasons. Primarily, number one, because it’s a Neolithic food, meaning it was not consumed during the Paleolithic era and, therefore, it’s not part of our evolutionary heritage. And then [also] because of proposed physiological mechanisms by which dairy causes harm when it’s consumed, like inflammation as an example. On the other end of the spectrum, you have the conventional medical view that dairy is healthy when it’s well-tolerated. You have the Weston A. Price Foundation [and] Nourishing Traditions, who’ve advocated for full-fat, often raw, dairy products and [the] health benefits there. [You have] researchers like Stephan Guyenet, Chris Masterjohn, Kurt Harris, who’s not really writing anymore in the health world but used to, and people like myself. In my first book, The Paleo Cure, I argued that dairy can be part of a healthy, whole foods diet if it’s well-tolerated.
Rather than just share [my] opinion about this topic, I want to review the research and what the research says. Before I do that, I want to address one of the arguments that’s often made as to why we shouldn’t eat dairy products. I think it’s a worthless argument, but it’s one that I hear often, so I just want to bring it up before we dive into the research and the details. This is particularly common in the vegan community and the raw food vegan community, but I’ve heard it from other people, too. [The argument] is that humans should not consume dairy products because we are the only mammal that drinks milk into adulthood. As you probably know, most mammals, including humans, prior to about 10,000 [or] 12,000 years ago, only consumed milk from their mother prior to being weaned. Once we were weaned, we didn’t go on consuming dairy products after that. So the claim is that, because of that, we shouldn’t consume milk or dairy products.
The problem with that argument is [that] there are lots of things that humans do now that no other mammals do. In the world of eating, a good example would be dark chocolate. We consume dark chocolate. I don’t know of any other mammals or animals out there that are cultivating and producing their own chocolate and eating it. But we do, and it seems to have many health benefits, if you look at the research. We cook our food. That’s another example. I don’t know any other mammals or animals that are cooking food, yet cooking food has been shown to increase nutrient absorption and provide many health benefits. Some scientists even believe that cooking food is part of what made us human because it enabled us to extract more nutrients more quickly, spend less of our time gathering and eating food, and led to [a] larger brain and the intelligence that distinguishes us from other animals. We also fly on airplanes, we drive cars, [and] we use phones. Certainly, some of those things have downsides, but they also have tremendous benefits. So I don’t think it’s a very good argument that we shouldn’t do something just because other mammals or animals aren’t doing it. I just wanted to start there.
Background of Dairy Consumption By Humans
Let’s talk a little bit about the background of dairy consumption among humans because I think that’s important to set the stage. Dairy product consumption didn’t begin until about 10,000 to 12,000 years ago. So it’s true [that] it’s a Neolithic food [and] was not part of our habitual food consumption during the Paleolithic era. But there was a reason that dairy products started to be consumed, and this is true for most behaviors that are preserved, from an evolutionary perspective—they serve some purpose, or they wouldn’t continue. It seems, from the most recent research, that the consumption of dairy arose in different parts of the world separately, or distinctly. One was the Middle East; another was East Africa. At least those two. Dairy products provided a great source of hydration, which would have been protective during periods of drought, and [they] also provided a meaningful source of calories and nutrition. In those parts of the world where people began to consume dairy products, that behavior was preserved over time and then spread to other parts of the world.
Now, it is true that human beings require a particular enzyme called lactase to digest the sugar in milk, lactose. Prior to the emergence of dairy consumption in those areas, humans only produced lactase when we were babies, prior to being weaned, because mother’s milk was the only source of milk in the diet. Once we were weaned, we didn’t need to continue to produce lactase. The body would just shut that [production] down, and we would not be able to digest milk into adulthood. And today, that’s still true for two-thirds of the global population. In other words, only about 35 percent of the population around the world continues to produce lactase into adulthood and is thus able to digest lactose, the sugar in milk. We’re going to talk a little bit more about this later in the show. But it’s worth just pointing out briefly that even if you’re one of the 65 percent that doesn’t produce lactase in adulthood, that doesn’t mean that you can’t enjoy dairy products. There are many ways that you can still benefit from dairy, if you choose to, even if you can’t digest lactose. So, after around 10,000 [to] 12,000 years ago, we had [the] first emergence of pastoralist cultures that raised animals for milk, and then that spread to other parts of the world, particularly Northern Europe and Scandinavia, where today, about 95 percent of people are lactose tolerant because they produce the lactase enzyme into adulthood. So your personal tolerance of lactose, the sugar in milk, will depend on your genetic heritage. Of course, that’s not black or white, because we are a true melting pot. In most places in the world, most people have mixed genetic heritage. You can think of lactose tolerance as more of a spectrum, [rather] than an off-on, black-white, binary function. Most people fall somewhere on that spectrum. Some people are completely tolerant of lactose. Other people are completely intolerant to the point where, even if they have a minute or small amount, they have trouble. Many people are somewhere in between, and it’s more of a threshold-based tolerance, where they can tolerate some amount of lactose, but if they consume a whole bunch of it, they don’t do well. That’s what I’ve seen in my clinical practice working with thousands of patients over the years and the feedback I’ve gotten from the thousands of healthcare practitioners that I’ve trained, as well.
The Research on Dairy Consumption
So with all of that context in mind, let’s move into talking a little bit about the research. Loren Cordain’s group published some review papers proposing various physiological mechanisms by which dairy causes harm. One was a paper by Melnik called “Milk signalling in the pathogenesis of type 2 diabetes.” They present a theory that milk consumption beyond the weaning period could overstimulate pancreatic beta-cells and promote beta-cell death. And since the proliferation and death of beta-cells are hallmarks of type 2 diabetes, it follows that milk consumption must contribute to type 2 diabetes. But if that theory was true, we would expect to see increased rates of type 2 diabetes in people consuming dairy products. In fact, we don’t see that, and we often see the opposite. For example, one study looked at serum levels of trans-palmitoleic acid, which is a fatty acid found in dairy fat, and correlated those levels with risk factors for diabetes. They found that higher circulating levels of trans-palmitoleic acid were associated with healthier levels of blood cholesterol, inflammatory markers, insulin levels, [and] insulin sensitivity, even after adjustment for other risk factors. During the follow-up period, people with higher circulating levels of trans-palmitoleic acid had a much lower risk of developing diabetes, with about 60 percent lower risk among participants in the highest quintile of trans-palmitoleic acid levels, compared to people in the lowest quintile. Put more simply, this study directly contradicted the theory that was posed in [the] milk signaling paper, and found that people with the highest levels of this particular fatty acid from dairy products had about one-third the risk of developing diabetes over a three-year period. I’m going to cover some more studies that clearly show that dairy products either don’t increase the risk of diabetes or reduce it.
Another study found that people with the highest levels of milk fat biomarkers were at lower risk of heart attack. For women, the risk was reduced by 26 percent, and for men, it was 9 percent lower. Another study showed that people who ate the most full-fat dairy had a 69 percent lower risk of death from cardiovascular disease than those who ate the least. And then a large review of 10 studies found that drinking milk was associated with a small but significant reduction in heart disease and stroke risk. This is research from the 2010 to 2015 period. I want to review some more recent research to give you an idea of what the studies over the past five to 10 years have shown, as well.
There’s a paper that was published in Advances in Nutrition in 2016 called “Comprehensive Review of the Impact of Dairy Foods and Dairy Fat on Cardiometabolic Risk.” I’m going to quote from this paper because it’s pretty straightforward. “This comprehensive assessment of evidence from RCTs suggests that there is no apparent risk of potential harmful effects of dairy consumption, irrespective of the content of dairy fat, on a large array of cardiometabolic variables, including lipid-related risk factors, blood pressure, inflammation, insulin resistance, and vascular function. This suggests that the purported detrimental effects of saturated fatty acids on cardiometabolic health may in fact be nullified when they are consumed as part of complex food matrices such as those in cheese and other dairy foods. Thus, the focus on low-fat dairy products in current guidelines apparently is not entirely supported by the existing literature and may need to be revisited on the basis of this evidence.” So, [there are] several interesting things about this paper and this conclusion. Number one, no harmful effect of dairy products for cardiometabolic risk factors. In fact, in many of the studies that they reviewed, they saw benefits and improvements [in] people consuming dairy. The second interesting point is that low-fat or nonfat dairy was not better than full-fat dairy. In many cases, actually, full-fat dairy shows more benefits and improvements than nonfat and low-fat dairy. I think the reason for that is what we just reviewed. There are some fatty acids in full-fat dairy products, like trans-palmitoleic acid, but also conjugated linoleic acid and a few others, that seem to have particular benefits. I’m going to cover these in more detail shortly, but I just wanted to point that out as we reviewed this paper.
There was another study a couple [of] years earlier that [was] published in the European Journal of Nutrition by Stephan Guyenet, who’s a friend and colleague. He was at the University of Washington at the time, [and] a PhD who studied the neurobiological regulation of fat mass. They reviewed 16 studies and found that high-fat dairy intake was inversely associated with measures of adiposity. Inversely associated means that people who consumed more high-fat dairy had better metabolic health, in this case. This association was not seen with nonfat or low-fat dairy. That’s a very interesting finding. Another paper [was] published more recently in the journal Advances in Nutrition in 2019 called “Effects of Full-Fat and Fermented Dairy Products on Cardiometabolic Disease.” I’m going to quote directly from the abstract here because it’s quite clear. “In fact, the weight of evidence from recent large and well-controlled studies, systematic reviews, and meta-analyses of both observational studies and randomized controlled trials indicates that full-fat dairy products, particularly yogurt and cheese, do not exert the detrimental effects on insulin sensitivity, blood lipid profile, and blood pressure as previously predicted on the basis of their sodium and saturated fat contents; they do not increase cardiometabolic disease risk and may in fact protect against cardiovascular disease and type 2 diabetes.” [It] can’t get more clear than that. [It’s] yet another paper, a large meta-analysis of other reviews, finding that full-fat dairy not only doesn’t increase inflammation or harm metabolic or cardiovascular health, [but] it generally improves it.
The last paper I want to talk about was a randomized control[led] trial from [the] American Journal of Clinical Nutrition[in] 2021. It’s called “Impact of low-fat and full-fat dairy foods on fasting lipid profile and blood pressure.” This was a trial of about 70 participants, where they had a four-week run-in period with limited dairy intake. Then they randomly assigned people to one of three diets—either containing a limited dairy diet, or switching to one with almost three and a half servings of either low-fat or full-fat milk, yogurt, and cheese for 12 weeks. They measured a bunch of markers and found that, in men and women with metabolic syndrome, a diet rich in full-fat dairy had no effects on fasting lipid profile or blood pressure, compared with diets limited in dairy or rich in low-fat dairy. Therefore, dairy fat, when consumed as part of complex whole foods, does not adversely impact these classic cardiovascular disease risk factors.
I could go on. I’m just sharing a selection of the research to give you an idea, but there are tens, if not hundreds, of studies investigating this question. And as I’ve indicated from the reviews and meta-analyses that I’ve shared, the conclusion is quite clear. Dairy products, and full-fat fermented dairy products in particular, seem to have benefits for cardiometabolic function and several other markers of health.
The majority of evidence indicates that conventional wisdom may actually be right about dairy. #chriskresser #dairy #bonehealth
Benefits of Full-Fat Dairy
So, why would that be? Why would full-fat dairy, in particular, be more beneficial than nonfat and low-fat dairy? Well, we already talked about it a little bit. Some of the fatty acids in dairy products, like trans-palmitoleic acid, seem to have unique health benefits. We also know that some of the compounds that are present in high-fat dairy products, like butyrate and conjugated linoleic acid, have benefits that, over the past few years, have become much more clear. Butyrate provides energy to the cells lining the colon, it inhibits inflammation, which may explain why dairy is not inflammatory, and [it] may prevent colonic bacteria from entering the bloodstream. In fact, butyrate’s anti-inflammatory effect is so strong that we use it in Functional Medicine, and even in conventional medicine, to treat serious inflammatory bowel diseases like Crohn’s disease. One trial showed that 4 grams per day of butyrate for eight weeks induced complete remission in a group of [patients with] Crohn’s disease. Another fatty acid in milkfat is called phytanic acid, and it’s been shown to reduce triglycerides, improve insulin sensitivity, and improve blood sugar regulation in animal models. Conjugated linoleic acid is a natural trans fat found in dairy products. I know you’re probably familiar with artificial trans fats, which are very harmful. But conjugated linoleic acid is a natural trans fat, and it’s been shown to reduce the risk of heart disease, cancer, and diabetes. Dairy fat is also a good source of fat-soluble vitamins like retinol, preformed vitamin A, and vitamin K2 when it comes from grass-fed cows, and those can be difficult to find elsewhere in the diet. And then, of course, dairy is a good source of other nutrients like bioavailable calcium.
Most people do not get enough calcium in [their] diet, and there aren’t very many good sources of bioavailable calcium. On paper, dark leafy greens, like spinach, are a good source. For example, one serving of spinach contains about 115 milligrams of calcium. But what the food label won’t tell you is that the bioavailability of calcium in spinach is extremely low. It’s about 5 percent. So you’re only going to absorb about 6 milligrams of that 115 milligrams of calcium in that spinach, whereas the bioavailability of calcium in milk is on the order of 30 to 40 percent. This means you’d have to consume 16 cups of spinach to get the same bioavailable calcium that you get from one glass of milk.
Now, I know some of you are thinking, “But I can’t drink milk. I don’t feel good.” We’re going to talk about that, because it’s true. Milk and dairy are not appropriate for everybody. But for those [who] can tolerate dairy, this is the main point I’m trying to make with this podcast—if you can consume dairy products and you feel good and you’re not lactose intolerant, and you’re not sensitive to the proteins in dairy products, the research overwhelmingly shows that it’s a beneficial food, particularly when you consume high-fat dairy products, and particularly when you consume organic dairy products from animals that have been grass-fed and raised on pasture without hormones, antibiotics, GMO food, etc. The question of raw dairy, and A2 versus A1, those are other topics, which I’m not going to cover in this show. I’ve talked about those before. But there are ways of making dairy products even more health-promoting.
The False Criticism That Dairy Has a Negative Impact on Bone Health
Now that we’ve covered the research on dairy products in general for cardiometabolic health, inflammation, insulin, [and] heart disease, [and] we’ve talked about why full-fat dairy tends to be more beneficial for cardiometabolic health due to the unique compounds that it contains, I want to talk about another criticism of dairy products, which is that consuming dairy has a negative impact on bone health. After that, we’re going to talk a little bit about some of the practicalities, like how to know if you’re intolerant to lactose or the proteins in dairy and how to address that in the diet.
The claim that dairy products contribute to osteopenia and osteoporosis is largely based [on] the acid-alkaline hypothesis. I’ve debunked the acid-alkaline hypothesis in general on my podcast, [and] also [in] blog articles. I really encourage you to search for “Chris Kresser, acid-alkaline” if you haven’t seen or listened to that content and if you still believe that the acid and alkaline content of foods that we eat makes a significant impact on our health, because there’s no evidence to support that and lots of evidence that contradicts it. I’m going to focus right now on the specific claim that dairy products acidify our bodies and contribute to osteopenia and osteoporosis.
So, again, this claim is based on the acid-ash hypothesis of osteoporosis. The idea is that, when we consume foods that are high in phosphate, they leave an acid ash after digestion, which lowers the pH of our blood, and then the body supposedly compensates for this to restore normal blood pH by stealing alkaline minerals like calcium from the bones, which then decreases bone density. There are several problems with this hypothesis, and we can use a 2011 study that specifically addresses the dairy, acid balance, [and] osteoporosis connection to highlight those. The study is called “Milk and acid-base balance: proposed hypothesis versus scientific evidence,” and the authors reviewed both the acid-ash hypothesis, in general, and the specific claim that dairy contributes to osteoporosis. Not surprisingly, after reviewing the evidence, they reached the same conclusions that I have. The studies just don’t support this hypothesis. First, they emphasize that urine pH is not indicative of systemic pH. In fact, except in cases of serious renal insufficiency [or] kidney disease, diet has no impact on serum pH. If it did, we’d be in a lot of trouble because the pH of our blood is maintained in a very tight range and if it deviates significantly, we can die. If human beings had to carefully monitor the acid-alkaline content of their diet, we would not have survived this long, because as you know, our distant ancestors didn’t have any concept of acid-alkaline balance. There were periods of varying food availability, [and] it wouldn’t make sense from an evolutionary perspective that we could so easily alter such a critical factor that would determine our survival [just] by [shifting] what we eat.
Second, the bones don’t even come into play in the regulation of serum pH. That’s the job of the kidneys. Any acid ash that’s left behind by the foods we eat can be easily dealt with and eliminated in the urine. This is why your urine changes pH depending on what you eat. It’s a sign that your kidneys are doing their job. That’s important to understand because advocates of this hypothesis often recommend or even sell urine pH tests, and they claim that if the pH of your urine is low, that means your body is acidified and you need to consume a bunch of alkaline foods. That can lead to changes in urine pH, but that doesn’t mean anything is changing with your serum pH, or that it’s having any impact on your bone health or overall health. What’s also particularly interesting is that, even if you accept this acid-alkaline hypothesis in general, the authors of this paper cite two studies that indicate that milk actually leaves an alkaline ash, as opposed to an acid ash, based on measurements of urine pH and net acid excretion following milk consumption in clinical trials. So, even if we go with the acid-alkaline hypothesis, this study found that milk is an alkaline food, not an acid-forming food. The whole hypothesis just completely falls apart when you really look at the evidence.
Perhaps even more important, it’s helpful to look at evidence that links dairy consumption directly to bone health. Instead of coming up with a proposed mechanism like the acid-alkaline hypothesis and looking at that intermediary mechanism, it’s best to go right to the direct clinical endpoint that we’re concerned with, which is bone health. So, what do studies that have looked at this show? Well, they show that drinking milk tends to lead to positive calcium balance, meaning more calcium is absorbed than excreted. Other studies show that phosphate, which is in milk products but also in other foods, increases calcium retention and improves bone health, which is why phosphate is found in lots of bone health supplements. Increased dairy consumption is consistently associated with lower rates of osteopenia, osteoporosis, and better bone health across many different cultures around the world. For example, increased dairy intake in postmenopausal Korean women was associated with a decreased risk of osteoporosis. Another study found that in the [United States], dairy intake was a significant predictor of osteoporosis among postmenopausal women, meaning women who consume more dairy had lower rates of osteoporosis. And in Poland, higher dairy consumption during childhood and adolescence predicted better bone health in adults. Again, these are just three studies I’m picking that are representative. There are many other studies in the scientific literature that support the connection between dairy consumption and better bone health.
All right, so that’s what the research says. It’s pretty convincing, especially if you review the bulk of the evidence [and] not just these studies that I’ve selected. But I chose ones that were representative. I chose large, systematic reviews that looked at all different types of evidence, other reviews, randomized controlled trials, observational data, prospective studies, retrospective analyses, etc., and they all point to the same conclusion—that dairy consumption, particularly full-fat dairy, is beneficial for cardiometabolic and bone health.
The Practicalities of Dairy Consumption
Now that we’ve reviewed the evidence, let’s talk about some of the practicalities. It is true that many people do not tolerate dairy products well, and there are two reasons for this. One is that some people are intolerant of the proteins in dairy products and can have an [immunoglobulin G] (IgG)-mediated intolerance, which can be mild to serious but is not a true allergy. Or, some people can actually be allergic to the proteins in dairy. This is fairly uncommon, actually. The prevalence studies I’ve seen range a bit, but it’s generally in the 1 to 3 percent range from what I’ve seen. Whereas lactose intolerance, [which is] the inability to digest the sugar in milk, is much more common, as we discussed earlier in the show. That affects two thirds of the global population. However, even if someone is lactose intolerant, that doesn’t mean that they can’t enjoy some dairy products. Ghee has virtually no lactose in it. Butter has very little lactose. Hard cheeses, particularly those that have been aged for a while like cheddar, have almost no lactose. Even full-fat whipping cream is fairly low in lactose. Then as you go down the line, you have soft cheese and fluid milk, which are quite high in lactose. [With] yogurt and fermented dairy, the lactose content in those products can vary depending on how long they’ve been fermented. The longer they’ve been fermented, the lower the lactose content. Twenty-four-hour, at-home fermented yogurt or kefir will often be virtually free of lactose. As you can see, there are many different options for dairy products for people who want to get the benefits of calcium, the fatty acids that are in dairy fat, and the other nutritional benefits of dairy, in addition to the delicious taste. For people who like dairy products, even if you’re lactose intolerant, you can still enjoy those products. And your mileage will vary. For some people, if they’re extremely lactose intolerant, they may not be able to consume [many] of those products, even the ones that are low in lactose. But for others, they can eat quite a bit of those products and not have an issue.
Speaking personally, I don’t do well with fluid milk, too much soft cheese, or store-bought yogurt. But I can have hard cheese, ghee, butter, cream, and homemade yogurt and kefir all day long with no problem at all. If you’re intolerant of the protein in dairy, that’s a little bit more challenging, because almost all dairy products contain dairy protein. The exception would be ghee. Butter is fairly low in protein, as well, but definitely, if someone’s allergic to the protein, they’re not going to be able to tolerate butter, usually. They may be able to tolerate ghee if it’s just an intolerance, rather than an allergy. It will depend on how significant the intolerance is. In terms of testing, there are some tests out there to screen for dairy protein intolerance or allergy. A typical food allergy test should test for dairy proteins. In terms of intolerance, there are labs like Cyrex, [whose] Array 4 panel is good for dairy proteins. Vibrant Wellness has a food intolerance test that screens for dairy proteins, as well. If you work with a Functional or integrative medicine practitioner, you can probably ask them to order those tests. If you want to know about your protein tolerance when it comes to lactose intolerance, there are also tests out there [for that]. But I’ve found that the best and most effective method, because it’s more of a threshold-based condition rather than just a black or white binary thing, is an elimination provocation protocol. You remove all dairy products from your diet for a period of time, and then you start to add them back in, in descending order of lactose content. So you’d start with ghee. Most people will be fine with that, even people [who] are extremely lactose intolerant. Then you go to butter, then you could go to hard cheeses, which are almost free of lactose, [and] then you could go to 24-hour, at-home homemade kefir or homemade yogurt. If you still do well with that, you could go to store-bought yogurt and store-bought kefir, and so on down the line, soft cheese, fluid milk, etc. If you’re fine with ghee and butter and hard cheese, but then at some point, you start reacting to dairy products, maybe when you start consuming yogurt from the store or fluid milk, then you know you have some level of lactose tolerance. If you were intolerant of proteins, you would have reacted to the hard cheese because it’s virtually free of lactose but has plenty of dairy protein. Hard cheese can be a good benchmark for differentiating between lactose intolerance and protein intolerance. That’s the general process I use in my practice with patients. It works pretty well, and since everyone’s sensitivity tends to be pretty individual, it’s often even more effective than doing the tests.
I hope this was helpful [and] I hope you learned something. It’s interesting to me that dairy products are so hated in the alternative, Functional [Medicine], [and] Paleo communities, because when you look at the scientific evidence, it’s clearly beneficial from a health perspective, if it is well tolerated. So, that’s the crux of it. I do think it’s worth pointing out that, in all of the studies that I mentioned, they didn’t segment people according to their tolerance of lactose or dairy proteins, and they just took a broad sample of people. I think we can almost guarantee that there were people in those studies [who] were lactose intolerant or were intolerant to the proteins in dairy, and yet [they] still experienced some of those cardiometabolic benefits. That’s interesting to me. I’m not suggesting that people who are intolerant of dairy should consume it. I don’t think that they should, because I think it could be problematic in those cases. I’m just pointing out that even without segmenting people, those studies still showed benefit. If they had segmented people, perhaps they would have shown even more benefit.
I’m going to put some links to articles I’ve written on this topic with more information and scientific references [in the show notes]. I’ll also put links to some of the references that I brought up in the show that aren’t present in those articles. You can always check out the show notes to get this information [for] any episode of the show. Once again, I want to thank you for listening. Please keep sending your questions to ChrisKresser.com/podcastquestion, and I’ll see you next time.
This episode of Revolution Health Radio is sponsored by Inside Tracker, Zero Acre Farms, and Paleovalley.
As a member of our community, Zero Acre Farms has a very special offer for you. Go to ZeroAcre.com/Chris or use code CHRIS at checkout for free shipping on your first order.
Inside Tracker has an exclusive offer for Revolution Health Radio listeners. Visit Insidetracker.com/chriskresser and get 20% off everything in the store when you sign up.
Paleovalley is also offering our listeners a special deal. Head over to Paleovalley.com/Chris and use the code KRESSER15 to get 15% off your order.