So it turns out that ice cream is actually... healthy? The biggest paradox in nutrition science
- Michelle Adams
- Mar 20
- 9 min read
You can listen to the video version of this article here.
If I ask you to name five foods that you should include in a healthy diet, you would likely say something like: fruits, vegetables, nuts, fish, wheat bread, and so forth. Those foods are all nutritionally dense, but, there is one food that has been scientifically linked to a lower risk of heart disease and diabetes that you likely would not even think to mention. From the title of this article, you can guess what that food is – ice cream.
I know that this seems like a joke, but I promise you that it isn't. Ice cream, full of sugar and saturated fat, has been shown to be “healthy.” How is this possible? To understand this paradox, we’ll have to see what the data have to say. For that, we will need to time travel back to the 1980s, when the very first study on this topic was conducted.
The 1980s - The birth of the ice cream paradox
In 1986, scientists at Harvard sent out surveys to tens of thousands of men as part of the Health Professionals Follow-up Study. The purpose of this study was to better understand how what we eat could impact our risk of developing chronic illnesses like heart disease, cancer, and diabetes. The men in the study, who were mostly white, middle-aged, and financially well-off, were followed for 12 years. As part of this study, they were asked to complete a food frequency questionnaire, which is basically a catalog of different foods and food groups that provides insight into people’s dietary habits. Ice cream intake was part of this questionnaire. When researchers analyzed the data on who developed diabetes and who ate ice cream, they found something unexpected – that those who ate ice cream 2 or more times per week were the least likely to develop diabetes. Unexpected or not, this was a statistically significant finding. Nevertheless, it was left out of the abstract and not really discussed in the paper. You have to dig way into the parts of a research paper that, let’s face it, most people are not going to read, to find this information. It's kind of strange. Did the researchers feel conflicted by the finding? Did they think it was a mistake?
Were they worried that people everywhere would start eating ice cream for breakfast every day if word got out that ice cream was correlated with positive health effects? Who knows.
Let’s move on to the next study.
The 1990s - Women get a chance in the spotlight
Harvard, in conjunction with Brigham and Women’s Hospital, launched The Women’s Health Study in 1993. This study, unlike the first, focused on women – about 40,000 of them. Like the first study though, the pool of study participants was not very diverse; these study participants were mostly white and middle-aged. After observing these women’s dietary habits and checking to see who developed diabetes, the scientists found... nothing. At this point, ice cream seemed to have a beneficial effect for men, but not for women.
The 2010s - The data just keeps coming
In 2014, a study that was bigger than either of the previous two was published. It pooled data from 3 large studies, and included about 40,000 men (which was actually data from the first study I talked about) and over 150,000 women. Over the duration of the study period, over 15,000 participants developed type 2 diabetes. So, what do you think they found? Did ice cream once again prove to be a health-promoting food?
Yes, it did.
A higher intake of ice cream was significantly associated with a lower risk of developing Type 2 diabetes - again. But, you wouldn’t know this just from reading the abstract. In this study, both ice cream and yogurt were found to be linked to a lower chance of developing diabetes, but only yogurt is mentioned in the conclusion. Ice cream gets ignored completely! You would have to actually read the research paper – which, again, most people are not going to do – to see these shocking results.
It really is starting to feel like a cover up.
The authors tried to make sense of this finding using something called “reverse causation.” Reverse causation is a term used in research to describe when a result is caused by a change in the participants’ behavior that makes it such that the original cause and effect association that you were looking for becomes hard to measure. Let’s look at a specific example that relates to these ice cream shenanigans. If you eat ice cream and French fries every day, and then you get diagnosed with high cholesterol, you might start eating less ice cream and French fries and start eating more salads and fruit. It takes time to lower your cholesterol, so the effects of your new diet won't be evident right away. Now, let's say you decide to join a research study. Your cholesterol is still high, as you are still in the early days of working on your diet. If the researchers asked you what you ate in order to understand why you have high cholesterol, and you told them that your diet is mainly salads and fruit, that would make it seem as though salads and fruit cause high cholesterol when in reality it was your old diet of ice cream and French fries.
But, here’s the thing.
Even when the scientists tried to account for such possible behavior changes, ice cream was STILL shown to be significantly linked to a lower risk of diabetes. This finding was supported by more studies that came out in 2013 (and this one), 2016, and 2019.
Ice cream is not only is linked to a lower risk of diabetes, but also a lower risk of heart disease
The whole idea that ice cream could be healthy remained buried until 2019, when a PhD student at Harvard named Ardisson Korat shared the findings of his research looking at the link between dietary fat intake and the risk of developing type 2 diabetes. Now, dissertations do not normally get turned into news headlines, but somehow, this one did. The Atlantic, The Public Broadcasting Service, better known as PBS, and The Guardian all ran stories on this conundrum.
Ardisson hadn’t simply published more of the same research that people had been ignoring. Instead, he found something new and even more preposterous – that ice cream could protect against heart disease. More specifically, he found that 1/2 cup of ice cream per day (equal to 1 serving) was linked to a lower risk of cardiovascular disease. It was already crazy to think that a sugary food could protect against diabetes, and now, the research was showing that a food high in saturated fat could protect against heart disease! Side note – the whole idea that saturated fat causes heart disease has been disputed, but that is a scandal on its own that will require its own post.
Why might ice cream have health benefits?
What is in ice cream that could make it good for us? Various suggestions have been proposed in the research papers referenced above and from experts like Dariush Mozaffarian, who is both a medical doctor and a doctor of public health.
There are 3 prevailing theories:
People who eat ice cream also engage in other behaviors that lower their risk for diabetes.
People who avoid ice cream may engage in other behaviors that increase their diabetes risk.
Ice cream has benefits that are as of yet unknown to us; perhaps the milk fat globule membrane (MFGM), which may help protect against high cholesterol, may be playing a role. This is hard to defend though, because other dairy foods like cream also have MFGM and have not shown the same associations with diabetes and heart disease that ice cream has.
No one knows for sure, though.
Since this is still a question that needs more research, I’m going to throw my own theories out there. Perhaps they will be tested some day.
My first theory is that ice cream is associated with being in a healthy psychological state. I would classify ice cream as a "fun food" - it's a food that we associate with a day at the park, the carnival, or the beach. Now, I know that ice cream can also be the thing you grab when you are home alone and depressed, but for the most part, I think we can say that ice cream is a food that we associate with good times. Perhaps that happiness effect is at play here, and it's the psychological benefits associated with being in a state of ease which may accompany indulging in a bowl of ice cream that we are actually seeing.
My second theory is that ice cream promotes mindful eating and portion control. Ice cream is cold, and that limits how much of it you consume in a single sitting before it turns into a milk shake. You have to eat it slowly and savor it – or suffer a brain freeze. The fact that you are forced to slowly enjoy it spoonful by spoonful, and that you cannot wolf it down like you would a sleeve of cookies or a bag of chips (or any other room temperature snack), means that you have to consume it with some level of mindfulness. I'm heavily theorizing here, but perhaps the low temperature at which ice cream is served aids in portion control and mindfulness, which are good eating habits to have.
My third theory is that people who eat ice cream eat are less afraid of eating a variety of fats, which broadly speaking is beneficial for your health. Going further on the theory that ice cream avoiders are somehow different from ice cream enjoyers, perhaps people who eat less ice cream also have a general phobia of consuming too much fat, which leads to them having a poorer diet quality. Starting back in the 1950s, the American public was given the message that saturated fat causes heart diseases. Considering that many participants in the research studies that were conducted in the 80s, 90s, and early 2000s likely heard this message or grew up with their parents passing that message on to them, it’s possible that many of them as adults still had that idea of "fat is bad" in the back of their minds. Shunning all fats is actually not beneficial for your health though, as fats play many essential roles in your body. My theory is that the ice cream eaters were the ones that said, "Screw the dietary guidelines! I’m going to enjoy ice cream, the full fat kind not the fake stuff, steak, butter – fat in all its glory," and that made the difference.
Anyway, that’s my take on the ice cream paradox. If you have any theories – fun or serious – please share them in the comments below!
Take care.
References:
The studies on ice cream:
Choi HK, Willett WC, Stampfer MJ, Rimm E, Hu FB. Dairy consumption and risk of type 2 diabetes mellitus in men: a prospective study. Arch Intern Med. 2005 May 9;165(9):997-1003. doi: 10.1001/archinte.165.9.997. PMID: 15883237.
Liu S, Choi HK, Ford E, Song Y, Klevak A, Buring JE, Manson JE. A prospective study of dairy intake and the risk of type 2 diabetes in women. Diabetes Care. 2006 Jul;29(7):1579-84. doi: 10.2337/dc06-0256. PMID: 16801582.
Chen M, Sun Q, Giovannucci E, et al. Dairy consumption and risk of type 2 diabetes: 3 cohorts of US adults and an updated meta-analysis. BMC Med. 2014;12:215. doi:10.1186/s12916-014-0215-1
Gao D, Ning N, Wang C, Wang Y, Li Q, Meng Z, Liu Y, Li Q. Dairy products consumption and risk of type 2 diabetes: systematic review and dose-response meta-analysis. PLoS One. 2013 Sep 27;8(9):e73965. doi: 10.1371/journal.pone.0073965. PMID: 24086304; PMCID: PMC3785489.
Aune D, Norat T, Romundstad P, Vatten LJ. Dairy products and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of cohort studies. Am J Clin Nutr. 2013 Oct;98(4):1066-83. doi: 10.3945/ajcn.113.059030. Epub 2013 Aug 14. PMID: 23945722.
Gijsbers L, Ding EL, Malik VS, Goede J De, Geleijnse JM, Soedamah-muthu SS. Consumption of dairy foods and diabetes incidence : a dose-response meta-analysis of observational studies 1 , 2. Am J Clin Nutr. 2016;103:1111-11124. doi:10.3945/ajcn.115.123216.Am
Drouin-Chartier JP, Li Y, Ardisson Korat AV, Ding M, Lamarche B, Manson JE, Rimm EB, Willett WC, Hu FB. Changes in dairy product consumption and risk of type 2 diabetes: results from 3 large prospective cohorts of US men and women. Am J Clin Nutr. 2019 Nov 1;110(5):1201-1212. doi: 10.1093/ajcn/nqz180. PMID: 31504094; PMCID: PMC6821541.
Guo J, Givens DI, Astrup A, Bakker SJL, Goossens GH, Kratz M, Marette A, Pijl H, Soedamah-Muthu SS. The Impact of Dairy Products in the Development of Type 2 Diabetes: Where Does the Evidence Stand in 2019? Adv Nutr. 2019 Nov 1;10(6):1066-1075. doi: 10.1093/advances/nmz050. PMID: 31124561; PMCID: PMC6855942.
The dissertation:
Korat, Ardisson. (2018). Dairy Products and Cardiometabolic Health Outcomes. [Doctoral Dissertation, Harvard T.H. Chan School of Public Health]
News reports and interview:
Johns, D. M. (2023, April 13). Nutrition Science’s Most Preposterous Result: Could Ice Cream Possibly Be Good for You? The Atlantic. https://www.theatlantic.com/magazine/archive/2023/05/ice-cream-bad-for-you-health-study/673487/
Mellor, D. (2023, July 16). Analysis: Is it actually healthy to eat ice cream? Here’s what the evidence says. PBS NewsHour. https://www.pbs.org/newshour/science/analysis-is-it-actually-healthy-to-eat-ice-cream-heres-what-the-evidence-says
Bryant, M. (2023, April 15). Is ice-cream good for you? Scientists divided on claims about health benefits. The Observer. https://www.theguardian.com/society/2023/apr/15/is-ice-cream-good-for-you-uk-scientists-give-idea-cold-shoulder
Interview of Dariush Mozaffarian: Emanuel, G. (2023, June 6). Here’s the scoop on the new thinking about ice cream, yogurt, cheese and health. Www.wbur.org. https://www.wbur.org/news/2023/06/06/nutrician-ice-cream-dairy-dessert-recommendations
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