In 2024, headlines suggested that eating potatoes might lower the risk of heart disease and early death. The study behind those headlines was large, followed people for decades, and reported a statistically significant association.
It still did not show that potatoes help people live longer.
That distinction is the entire story. A large observational data set can estimate an association very precisely. It cannot turn a nonrandomized comparison into an experiment.
What the Norwegian study found
Researchers analyzed 77,297 adults who participated in Norwegian health screenings between 1974 and 1988. Participants reported their food intake, including how many potatoes they ate. The population was followed for a median of 33.5 years, during which 27,848 people died, including 9,072 deaths from cardiovascular disease.[1]
Compared with people reporting six or fewer potatoes per week, those reporting at least 14 potatoes per week had a 12% lower relative risk of death from any cause. In a continuous analysis, each additional 100 grams of potato per day was associated with about a 4% lower relative risk of all-cause and cardiovascular death.[1]
Those are the reported results. The original Disciple summary described the exposure as roughly 140 potatoes per month. That overstates what the main comparison actually tested. Fourteen potatoes per week is approximately 60 per month—not 140.
The study also examined a particular historical food culture. These were predominantly boiled potatoes eaten in Norway beginning in the 1970s and 1980s. The findings should not be casually translated to french fries, potato chips, restaurant meals, or a modern ultra-processed diet.
Why association is not intervention
The researchers did not randomly assign one group to eat potatoes and another group to avoid them. They observed people who had already chosen different diets and then used statistical models to adjust for measurable differences.
That leaves several problems that no sample size can completely solve.
People who eat different foods are different in other ways
Food choices cluster with income, education, smoking, physical activity, alcohol use, cooking habits, medication use, access to care, and the rest of the diet. Researchers can adjust for variables they measured well. They cannot perfectly remove variables measured poorly—or behaviors they never measured.
This is why nutritional epidemiology is especially vulnerable to healthy-user bias and residual confounding. A food can become a marker for the type of person, household, or dietary pattern in which it appears. In this historical Norwegian setting, frequent boiled-potato intake may have tracked a more traditional pattern of eating or another unmeasured behavior. That is a plausible interpretation, not something the study proved.
Food questionnaires are estimates
Diet was measured with semiquantitative food-frequency questionnaires. These tools are useful for studying large populations, but they depend on memory, portion estimates, stable habits, and a limited list of questions. Even repeated questionnaires cannot reconstruct decades of eating with laboratory precision.
More observations do not eliminate confounding
Seventy-seven thousand participants and nearly 28,000 deaths give the analysis statistical power. They do not provide randomization. A very large cohort can produce a narrow confidence interval around a biased estimate if the underlying groups differ in important unmeasured ways.
Large data sets improve precision. They do not automatically improve causal validity.
Other large studies do not show that potatoes are protective
If potatoes truly caused a meaningful reduction in mortality, we would expect that signal to appear reasonably consistently across other populations. It does not.
A 2021 analysis of 49,926 Norwegian adults in the HUNT3 study found no association between boiled-potato intake and all-cause or cardiovascular mortality over 10 years.[2]
A separate analysis combined two major US cohorts with a meta-analysis of 26 prospective studies. Higher total fruit and vegetable intake was associated with lower mortality, but potatoes were not. Starchy vegetables such as peas and corn also did not show the same pattern as most other fruit and vegetable groups.[3]
Another prospective analysis of 40,074 US adults found a 24% lower relative risk of mortality among people eating at least one serving of non-starchy vegetables per day compared with none. Potatoes, by contrast, had a null association with mortality (HR 0.93; 95% CI 0.82–1.06).[4]
These are still observational studies and deserve the same critical scrutiny. But taken together, they undermine the simple claim that potatoes themselves protect against death.
Starchy and non-starchy vegetables are not metabolically interchangeable
Calling a potato a vegetable does not make it nutritionally equivalent to leafy greens, broccoli, cauliflower, peppers, mushrooms, zucchini, or asparagus.
Potatoes are rich in starch. Their effect on blood glucose depends on the variety, preparation, portion, what accompanies the meal, and the person eating them. Non-starchy vegetables generally provide substantially less digestible carbohydrate per serving while delivering fiber, micronutrients, and a wide range of plant compounds.
That difference is visible even within large observational data sets: the association between non-starchy vegetable intake and better health outcomes is more consistent than the association for potatoes and other starchy vegetables.[3,4]
This does not make a potato poisonous, nor does it prove that every person must avoid one. It means potatoes should not inherit the health reputation of non-starchy vegetables merely because both appear in the produce section.
The more defensible conclusion
The Norwegian study is interesting because it shows how strongly context can shape a nutrition result. In one historical cohort, people who ate more predominantly boiled potatoes had lower observed mortality. The study cannot tell us that adding potatoes to a modern diet caused that difference.
So, no: potatoes do not help you live longer on the strength of this study.
The better lesson is methodological. Before changing how you eat because of a headline, ask whether the research was an intervention or an observation, how diet was measured, how different the comparison groups were, and whether other large studies found the same pattern.
That approach is less exciting than a miracle-food headline. It is also far more useful.
Watch the research discussion
References
- Arnesen EK, et al. Potato Consumption and All-Cause and Cardiovascular Disease Mortality—A Long-Term Follow-Up of a Norwegian Cohort. J Nutr. 2024;154(7):2226–2235. doi: 10.1016/j.tjnut.2024.05.011. PubMed.
- Moholdt T, Nilsen TIL. Frequency of Boiled Potato Consumption and All-Cause and Cardiovascular Disease Mortality in the Prospective Population-Based HUNT Study. Front Nutr. 2021;8:681365. doi: 10.3389/fnut.2021.681365. PubMed.
- Wang DD, Li Y, Bhupathiraju SN, et al. Fruit and Vegetable Intake and Mortality: Results From 2 Prospective Cohort Studies of US Men and Women and a Meta-Analysis of 26 Cohort Studies. Circulation. 2021;143(17):1642–1654. doi: 10.1161/CIRCULATIONAHA.120.048996. PubMed.
- Zhang T, Peng Z, Li H, et al. A prospective cohort study of starchy and non-starchy vegetable intake and mortality risk. Br J Nutr. 2023;130(4):719–727. doi: 10.1017/S0007114522003518. PubMed.
