Vegans Versus Meat Eaters Why the Latest Research Has No Simple Winner

The cancer findings that complicate the argument

In February 2026, the British Journal of Cancer published an analysis of more than 1.8 million people across nine prospective studies. Vegetarians had lower rates of five cancers, including breast and kidney cancer, but a higher rate of one type of oesophageal cancer.

The result most likely to alarm vegan readers concerned colorectal cancer: the vegan group had a 40% higher relative hazard than meat eaters.

However, only 8,849 participants were vegan, and that colorectal finding rested on 93 cases. When researchers excluded the first four years of follow-up, the association weakened and was no longer statistically significant.

This observational research cannot establish that avoiding animal foods caused cancer. Nor were its meat eaters necessarily heavy consumers: processed-meat intake was relatively modest.

The finding deserves investigation. It does not justify telling vegans to start eating steak.

In March, a separate review in the European Journal of Epidemiology reported a different-looking result. Across the studies contributing to its vegan total-cancer analysis, vegan diets were associated with a 23% lower relative risk than non-vegetarian diets.

The authors rated the evidence for a causal relationship between vegan diets and total cancer as “limited-suggestive”. That is a qualified finding, rather than proof that veganism prevents cancer.

These papers examined different combinations of studies and outcomes. A result for all cancers combined can also differ from a result for one particular cancer. Putting their headline percentages side by side as if they were opposing scores misses those distinctions.

The strongest argument for vegan diets still has limits

Randomised trials help answer a question that observational research struggles with: what happens when people are assigned to change their diets?

Stanford’s identical-twin trial, published in JAMA Network Open in 2023, remains a useful example. Researchers assigned 22 pairs of twins to healthy vegan or healthy omnivorous diets for eight weeks. Both approaches emphasised foods such as vegetables, whole grains and legumes.

Compared with the omnivorous group, the vegan group had a greater reduction in LDL cholesterol, with an estimated between-group difference in change of about 14 mg/dL. Fasting insulin and body weight also fell more.

Those are meaningful results. But 44 people followed for eight weeks cannot establish which diet produces fewer heart attacks over 20 years. The vegan participants also lost more weight, so the study does not isolate the effect of excluding animal foods from every other dietary change.

For someone interested in improving cholesterol, a thoughtfully constructed vegan diet is a credible option. The trial cannot promise the same result from any collection of foods carrying a vegan label.

A newer muscle study makes the practical problem clear

For an older adult, a falling number on the scale may deserve a closer look. Preserving muscle is a different objective from simply losing weight.

A trial published in the September 2026 issue of the American Journal of Clinical Nutrition followed 72 adults aged 65 or older for 12 weeks. Participants were assigned to their usual omnivorous diet, a self-selected vegan diet, or a self-selected vegan diet combined with resistance exercise.

In the vegan-only group, protein intake fell by roughly 19 grams a day by week 12. Participants lost thigh muscle volume and approximately 1.15 kilograms of appendicular lean mass, meaning lean tissue in the arms and legs. The omnivorous group’s appendicular lean mass remained broadly stable. Resistance exercise reduced, but did not eliminate, the losses in the vegan group.

The key detail is that participants selected their own food. This tested a dietary transition in which protein intake changed, rather than two diets supplying identical nutrition.

An earlier controlled crossover trial, published in the Journal of Nutrition’s April 2025 issue, studied 34 active older adults. Participants consumed vegan and omnivorous diets for 10 days each, with calories and protein matched. Researchers found no significant difference in daily muscle protein synthesis.

That short experiment did not establish equal muscle preservation over years. Taken together, the studies suggest a practical distinction: a vegan diet can supply the ingredients needed for muscle maintenance, but people do not necessarily replace those ingredients successfully when they remove familiar animal foods.

Imagine someone dropping eggs at breakfast, yoghurt at lunch and chicken at dinner. Toast, fruit and vegetable pasta may make an appealing menu, but the replacements need deliberate attention. Adding tofu, beans, lentils or other substantial protein sources is a different change from simply leaving the animal foods off the plate.

Plant based and minimally processed are not complete answers

The term “plant-based” can describe a bean stew, a bag of sweets or a diet that still contains some fish and meat. It is too broad to function as a nutritional rating.

A June 2026 study in The Lancet Regional Health – Europe adds another complication. Researchers analysed 124,836 UK Biobank participants, separating the nutritional quality of plant-based dietary patterns from their level of processing.

Healthier plant-based patterns were associated with better outcomes, including lower type 2 diabetes risk, whether their ultra-processed food content was relatively high or low. The authors suggested that overall nutritional quality might matter more than processing level for the outcomes studied.

This was observational evidence, and it does not make all ultra-processed foods equivalent. It does challenge the assumption that processing alone tells you everything useful about a product.

At the supermarket, compare what a food contributes. For a dairy replacement, look at protein and fortification. For a burger replacement, compare protein, saturated fat and salt per serving. The word “vegan” answers a question about ingredients; the nutrition panel answers different questions.

There is little practical value in rejecting a useful fortified product solely because it comes from a factory while overlooking the nutritional gaps in a menu made entirely from scratch.

Meat eaters do not get a free pass

Uncertainty about the best overall dietary label does not erase the evidence behind specific food recommendations.

The World Cancer Research Fund advises people who eat red meat to limit it to about three portions a week, equivalent to 350–500 grams cooked, and to eat little, if any, processed meat. The red-meat figure is a limit, not a minimum target.

A 150-gram cooked beef portion twice a week totals 300 grams. That is a very different pattern from daily bacon, lunchtime ham and frequent large steaks, although both people may describe themselves as meat eaters.

Red meat can provide protein, iron, zinc and vitamin B12. Those contributions do not make portion size or frequency irrelevant. Equally, a person can eat meat occasionally while building most meals around vegetables, beans and grains.

For someone with a daily processed-meat habit, changing that routine is a more concrete starting point than debating whether complete veganism is necessary. A lunch rotation of lentil soup, chickpea sandwiches and leftovers can reduce the frequency without requiring an entirely new food identity.

Vegan diets need a replacement plan

A successful switch involves replacing nutrients as well as recipes.

NHS guidance identifies vitamin B12, calcium, iron, iodine and selenium among the nutrients that can be missed in a poorly planned vegan diet. Fortified foods and, where appropriate, supplements help meet needs.

B12 deserves an explicit routine. Identify reliable fortified sources or an appropriate supplement rather than assuming vegetables will cover it. Nutritional yeast supplies B12 only when it is fortified.

For calcium, options include fortified plant drinks and calcium-set tofu. Check the actual label: products that look interchangeable may not supply the same nutrients. Iron from plants is absorbed less readily than iron from meat; pairing an iron-containing meal with vitamin C can help. Lentils with peppers or beans with broccoli are straightforward examples.

These are manageable tasks, but they still require attention. Someone planning a vegan diet during pregnancy, for a child, or alongside a medical condition has more to consider than an otherwise healthy adult changing a few dinners. A registered dietitian can help turn general advice into suitable meals.

What to change before choosing a side

Start with the meals you repeat. Breakfast eaten five times a week has more influence on your routine than a carefully photographed dinner once a month.

If you want to try vegan eating, redesign one complete meal before removing animal foods across the day. A vegetable stir-fry can include tofu, rice and a sauce you enjoy. A tomato pasta can become a lentil ragù. Decide what will replace your usual dairy foods and where B12 will come from.

If you want to keep meat, review its role. You could use a smaller amount in a bean chilli, alternate meat dishes with lentil or tofu dishes, and make processed meat an occasional choice. The useful measure is the pattern you repeat, rather than whether one dinner meets a particular label.

Also consider the effort involved. A plan requiring two separate dinners every night may be hard to maintain in a mixed household. A shared base of roasted vegetables, potatoes and salad, with beans, tofu, fish or chicken added according to preference, can make the change easier.

For older adults moving towards veganism, the recent muscle research gives a specific reason to check protein intake during the transition and discuss suitable resistance exercise. Waiting until strength or weight has noticeably changed is a less useful strategy than planning the replacements first.

None of these adjustments requires pretending that food preferences, budget or ethical beliefs are unimportant. They determine whether a menu is workable.

The latest evidence leaves room for more than one healthy way to eat. It also makes the demands of those choices clearer. Vegan diets require reliable nutrient planning; meat-containing diets require attention to the type, amount and frequency of meat. Both need to be judged by the food actually eaten and the health outcome being considered.

Before asking which side wins, look at an ordinary week of meals. That is where the useful changes become visible.