People do not necessarily have to eliminate pork to lose a meaningful amount of weight or improve the overall quality of their diet, according to a new analysis. But there is an important wrinkle: Participants who did not regularly eat pork lost considerably more weight.
The study, published in Nutrition & Diabetes, followed 187 adults with overweight or obesity who participated in a six-month WeightWatchers digital weight-management program. It was funded by the National Pork Board and WeightWatchers International Inc., and several researchers had financial ties to WeightWatchers or other food, pharmaceutical and health companies. Although the participants came from a randomized clinical trial, this particular analysis was observational. Researchers did not randomly assign people to eat or avoid pork, so the findings cannot show that pork consumption caused differences in weight loss or diet quality.
Researchers classified 147 participants, or nearly 79%, as habitual pork consumers because they continued reporting pork consumption in dietary recalls during the program. The remaining participants were classified as non-pork consumers.
Both groups lost weight over six months. Pork consumers lost an average of 5.3% of their starting body weight, roughly 10 pounds, an amount generally considered clinically meaningful. Participants who did not consume pork, however, lost an average of 8.6% of their starting weight.
Non-pork consumers were also more likely to achieve larger weight losses. They were about 4.7 times as likely as pork consumers to lose at least 10% of their starting body weight.
Those results make the study more complicated than simply concluding that pork fits comfortably into a weight-loss diet. Because participants chose what they ate, the researchers cannot determine whether avoiding pork contributed to greater weight loss or whether other differences between the groups were responsible.
“The study examined pork intake because pork is widely consumed but is often perceived as inconsistent with healthy eating or weight loss. We wanted to assess whether adults who continued reporting pork intake during a structured weight-management program could still achieve clinically meaningful weight loss while improving overall diet quality,” said lead author Ana M. Palacios of Georgia Southern University.
Diet quality also improved among pork consumers. Their average score on the Healthy Eating Index-2020, a measure of how closely a person's diet aligns with federal dietary recommendations, rose 4.3 points, from 55.0 at the beginning of the study to 59.2 after six months.
But there was no significant difference between pork and non-pork consumers in how much their diet quality improved. By the end of the study, average scores were similar between the two groups.
That suggests the clearest finding may be relatively modest: Continuing to eat pork did not prevent participants from improving either their weight or their overall dietary pattern while participating in a structured weight-management program.
The study cannot answer whether eating pork helped, hindered or had no meaningful effect on those outcomes.
Researchers also did not distinguish among different types of pork. Bacon, sausage, ham and lean cuts were all grouped under the broader category of pork consumption, even though their nutrient profiles and the foods typically eaten alongside them can differ considerably.
Dietary intake was based on participants' self-reported food recalls, which can introduce measurement error. The non-pork group was also much smaller than the pork-consuming group, with only 40 participants, limiting the strength of comparisons between them.
Because the analysis involved people already participating in a commercial weight-management program, the findings also may not apply to people attempting to lose weight on their own.
Taken together, the results provide some evidence against the idea that successful weight loss requires automatically putting pork off limits. They do not establish pork as a weight-loss food, however, and the greater weight loss seen among people who did not eat pork remains an important part of the picture.
The research was supported by the National Pork Board and WeightWatchers International Inc. Georgia Southern University, the Georgia Southern University Foundation, Indiana University and the Indiana University Foundation received funding from WeightWatchers to support the research. Several study authors were employees and/or shareholders of WeightWatchers when the study was conducted. Other disclosed relationships included employment, investments, payments or institutional research support involving Eli Lilly and Company, Kailera Therapeutics, General Mills, the American Egg Board, the National Cattlemen's Beef Association, the National Pork Board and numerous other commercial and nonprofit organizations.