Hot dogs, sausage, and . . . dementia? Harvard and MIT research links ultra-processed meat with new health concerns. – The Boston Globe

Regularly eating red meat has been linked with heart disease, diabetes, and several types of cancer. Now there’s fresh evidence tying some popular types of red meat to yet another health concern: it could be bad for your brain.A new study by Boston researchers finds that long-term consumption of processed red meat, such as hot dogs, sausage, and bacon, is linked to an elevated risk of dementia. The findings come on the heels of sobering research published on Monday from a separate team of scientists that estimates the number of Americans who develop dementia each year will double by 2060, to roughly 1 million new cases a year, largely because of the aging population.As scientists and policy makers search for ways to protect Americans’ health — and stave off chronic illnesses— attention is increasingly turning to reforming the American diet.AdvertisementIn the meat study, published online Wednesday in the journal Neurology,researchers at Harvard’s T.H. Chan School of Public Health and the Broad Institute of MIT and Harvard said they focused on processed red meat in hopes their findings would inform new dietary guidelines the federal government is developing and is expected to release later this year. In December, scientists advising federal health and agriculture agencies on the updated US Dietary Guidelines recommended they emphasize alternative sources of protein, such as beans, peas, and lentils, over red and processed meats.For red meat lovers, the latest Harvard study had some reassuring news: it did not find a significant increased risk of dementia from consuming “unprocessed” meat, such as ground beef or sirloin. But the scientists found that eating about two servings per week of processed red meat, which includes some cold cuts, correlated with a 13 percent higher risk of dementia compared to those who ate less than roughly three servings a month.The study also concluded that replacing a serving of processed red meat, equal to 3 ounces, with a serving of nuts or legumes per day might lower the risk of dementia by 19 percent, and by as much as 28 percent if the serving is replaced with fish.“We want to provide all these healthier alternatives for the general public, because we don’t want to just say, ‘Please eat less red meat,’ ” said lead author Dr. Daniel Wang, an assistant professor at Harvard Medical School and Brigham and Women’s Hospital. “We want to give a positive message, not just limiting people’s intake.”AdvertisementThe researchers analyzed data from two long-running health studies that included more than 130,000 participants and tracked them for up to 43 years, using regular food-frequency questionnaires to assess the association between red meat and dementia.Other researchers not involved in the study said the large number of participants and the lengthy time they were tracked is just the evidence regulators need to consider when setting food policies. But they cautioned that the study, like many other food tracking studies, relies on participants’ memories about what they ate, which can be fuzzy at times.In the second finding on dementia, which was published in Nature Medicine, researchers made the startling conclusion that roughly 40 (percent of people over age 55 will develop dementia in their lifetime. The estimate was based on data from another long-running study of more than 15,000 people across four states.“Our brain is a complex organ,” said Heather Snyder,the Alzheimer’s Association’s senior vice president of medical and scientific relations, who was not involved in either dementia study. “What may be contributing to a person’s [dementia] risk is likely a number of things, including the food that we may eat and ensuring that we have a balanced diet.”The association is conducting its own research on the links between dementia, diet, and lifestyle in a two-year effort called the US POINTER Study, with more than 2,000 participants in five sites across the United States. Results are expected to be reported in July.AdvertisementIn the meantime, the association, based on a multitude of other research, advises that healthier foods — vegetables and leaner meats and proteins, along with foods that are less processed and lower in fat — can reduce risk of cognitive decline.The public’s interest in “processed” and “ultra-processed” foods has surged since President-elect Donald Trump said he would nominate Robert F. Kennedy Jr., an outspoken critic of processed foods, to be health and human services secretary. But researchers and regulators also have many questions over exactly what these terms should mean and how those foods effect health.The panel advising the federal government on the next edition of the influential US Dietary Guidelines did not distinguish between unprocessed and processed red meat in its recommendations and concluded that more research was needed on health impacts from so-called ultra-processed food in general before further guidance in this category can be made. That is expected to delay substantial changes regarding such processed foods until the next update, in 2030.Ultra-processed foods is an imprecise term that generally means foods with many added ingredients like sugar, oils, fats, and artificial colors or preservatives.Many organizations reference a classification system called NOVA that breaks food into four categories based on how much they are processed. Fresh or frozen vegetables, grains, beans, and other minimally processed foods are considered the healthiest, while those in the bottom “ultra-processed” category, such as flavored yogurts, breakfast cereals, sweetened juices, ice cream, cookies, and more, the most unhealthy.AdvertisementBut Joanne Slavin, a professor of food science and nutrition at the University of Minnesota and a member of the 2010 advisory committee for the US Dietary Guidelines, said several seemingly healthy foods often get swept into an unhealthy category.“Whole grain breads are ultra-processed. Anything with four ingredients or more is ultra-processed,” Slavin said. “So then pretty much everything gets put into that fourth category, which, you know, wasn’t intentional, but that’s kind of where it ends up.”Susan Roberts, senior dean of research at the Geisel School of Medicine, Dartmouth College, who has also long studied nutrition, said there needs to be more scrutiny of the processed food classification system to better help the public make sense of how and what they should be eating.She said the recent advisory committee report on updating US dietary guidelines “did a good job of saying that ultra-processed foods, many of them, are likely to be bad, but the evidence for that as a category isn’t there yet.”Meanwhile, Slavin said she cautions consumers about information that lumps all ultra-processed food into the bad basket.“It’s like, ‘Never eat an ultra-processed food,’ when we haven’t even defined what an ultra-processed food really is, and that makes us look bad in the food and nutrition advice place,” she said. “And I don’t blame consumers for saying, ‘Hey, why don’t you guys get it figured out?’ ”Kay Lazar can be reached at kay.lazar@globe.com Follow her @GlobeKayLazar.Digital AccessHome DeliveryGift SubscriptionsLog InManage My AccountCustomer ServiceDelivery IssuesFeedbackHelp & FAQsStaff ListAdvertiseNewslettersView the ePaperOrder Back IssuesNews in EducationSearch the ArchivesPrivacy PolicyTerms of ServiceTerms of PurchaseContactWork at Boston Globe MediaInternship ProgramCo-op ProgramDo Not Sell My Personal Information

Source: https://www.bostonglobe.com/2025/01/15/metro/bacon-sausage-hot-dogs-ultra-processed-food-dementia/