In this study, researchers set out to compare the results of two diets that each followed the U.K.\u2019s nutritional guidelines, giving people their recommended servings of protein, fiber, and fruits and vegetables. But one diet was ultra-processed \u2014 think premade lasagna for dinner \u2014 while the other featured food prepared by an independent caterer, like spaghetti bolognese. The 50 study participants who completed the trial followed one diet for eight weeks, took a four-week break, and then switched to the other diet for another eight weeks.\u00a0<\/p>\n
In the end, both diets following the nutrition guidelines led to weight loss \u2014 but the minimally processed diet led to an average 2% reduction in weight, compared with a 1% reduction for the ultra-processed diet. (The people in the study didn\u2019t know that weight changes were the primary outcome being assessed and weren\u2019t told to change how they ate.) The minimally processed diet was also associated with greater fat mass loss, fewer cravings, and lower levels of triglycerides, a measure of heart disease risk, compared with the ultra-processed diet. The ultra-processed diet, however, was associated with lower levels of LDL cholesterol \u2014 the \u201cbad\u201d kind.<\/p>\n
The two main takeaways from these results, according to Sam Dicken, one of the study\u2019s co-authors and a research fellow at the University College London: First, following nutrition guidelines really can make a positive difference in people\u2019s health. (Research suggests that just 7% of the U.K. population<\/a> gets the amount of fiber recommended in dietary guidelines, while about a quarter get enough fruits and vegetables.) <\/p>\n \t\t\tFoods Second, Dicken said, \u201cwhen you\u2019re following that diet, minimally processed foods may have greater benefits.\u201d<\/p>\n To Christopher Gardner, a professor at the Stanford Prevention Research Center who was not involved in the study, it\u2019s worth stressing that people did lose weight when they ate ultra-processed foods that were consistent with dietary guidelines. (Before the study\u2019s onset, participants got an average 67% of their calories from ultra-processed foods and did not meet dietary guidelines except when it came to red meat.) To Gardner, that suggests it may not be ultra-processed food itself that\u2019s the problem \u2014 \u201cit\u2019s the junk that\u2019s the problem.\u201d\u00a0<\/p>\n The study\u2019s authors float several possible explanations as to why participants lost more weight on minimally processed foods. \u201cOne is calorie density,\u201d said Dicken. Healthier ultra-processed foods still tend to have more calories per bite than whole or minimally processed foods.\u00a0<\/p>\n Participants may have also eaten more on the ultra-processed food diet because they found the options more appetizing. They rated flavor and taste lower on the minimally processed diet, though they reported that the diets were equally satiating. And industrial processing itself may have been a factor \u2014 \u201cbreaking down and putting [ingredients] back together again, it may have been a bit of that as well,\u201d Dicken said.<\/p>\n All the food was delivered directly to the participants, allowing researchers to track results in a real-world setting while mitigating one of the most common pitfalls in nutrition research: Unless people are being monitored in a lab, it\u2019s hard to know for sure what and how much they\u2019re eating. Participants also recorded food diaries so researchers could monitor their adherence to the diet. Ultra-processed food researcher Kevin Hall<\/a>, whose lab experiments at the National Institutes of Health produced some of the best evidence<\/a> so far on the subject, helped design the study.<\/p>\n \t\t\t\t\t \t\t\t\t\t \t\t\t\t\t\t\t\t\t\tSign up for Morning Rounds<\/p>\n Understand how science, health policy, and medicine shape the world every day<\/p>\n Also noteworthy is the fact that even with food provided, people in the study had a harder time sticking with the minimally processed diet \u2014\u00a0\u201cwhich speaks to potential real world challenges that people may face\u201d in steering clear of ultra-processed foods, or UPFs, said Julia Wolfson, associate professor at Johns Hopkins Bloomberg School of Public, via email. She thinks public health messaging should acknowledge that, because of factors like cost, time, and accessibility, \u201cwe all consume at least some UPFs \u2026 so when you do, try to choose UPFs that are healthy as well.\u201d\u00a0<\/p>\n This was a small study of mostly women, and people who follow kosher, halal, or vegan diets were not included. The study\u2019s authors note that the fact that people lost weight by eating exclusively nutritious ultra-processed foods doesn\u2019t mean that others would benefit by doing the same if they don\u2019t eat much ultra-processed food currently.<\/p>\n The study\u2019s results may help inform the larger debate about how to improve the food environment, said Dicken. \u201cWe need healthier foods that meet dietary guidelines to be more accessible to people.\u201d That means addressing the financial barriers that can make less nutritious ultra-processed foods the more convenient and low-cost option for many.<\/p>\n As for the push to make ultra-processed foods healthier \u2014 whether by lowering sodium levels or, per the current craze<\/a>, adding protein in everything from waffles to ice cream \u2014 Dicken said there are limits to what that can achieve. \u201cFood reformulation can have beneficial effects,\u201d he said, \u201cbut it\u2019s not going to be the solution.\u201d<\/p>\n STAT\u2019s coverage of chronic health issues is supported by a grant from Bloomberg Philanthropies<\/a>. Our financial supporters<\/a> are not involved in any decisions about our journalism.<\/p>\n","protected":false},"excerpt":{"rendered":"Not all ultra-processed foods are bad for you. But if you\u2019re trying to lose weight, it\u2019s still probably…\n","protected":false},"author":3,"featured_media":118759,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[37],"tags":[210,1182,881,1183,67,132,68],"class_list":{"0":"post-118758","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-nutrition","8":"tag-health","9":"tag-nutrition","10":"tag-public-health","11":"tag-research","12":"tag-united-states","13":"tag-unitedstates","14":"tag-us"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/114971773665025024","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/118758","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=118758"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/118758\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/118759"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=118758"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=118758"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=118758"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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