Norwegian study finds that consuming potatoes lowers risk of cardiovascular disease and mortality

In a groundbreaking study, researchers in Norway have discovered that eating potatoes can significantly reduce the risk of cardiovascular disease and all-cause mortality. This study’s finding, challenges the common perception of potatoes as a less desirable vegetable due to their high starch content and glycemic index. The study’s results suggest that potatoes, particularly when boiled, offer notable health benefits that can contribute to a longer, healthier life.

A staple food with hidden health benefits

Potatoes have long been a staple in many traditional diets worldwide. They are rich in essential nutrients such as potassium, vitamin C, dietary fibre, and bioactive compounds, all of which are beneficial for cardiovascular health. Potassium helps regulate blood pressure, vitamin C functions as an antioxidant, and dietary fibres aid in digestion and weight management. These attributes make potatoes a nutritionally dense food option.

Despite these advantages, potatoes are often excluded from dietary recommendations due to their high glycemic index, which has been associated with an increased risk of cardiometabolic diseases. The glycemic index measures how quickly foods raise blood sugar levels, and high-GI foods can cause rapid spikes in blood sugar, potentially leading to insulin resistance and other metabolic issues.

However, the recent Nordic Nutrition Recommendations have hinted at including potatoes in regular diets, although no specific guidelines have been provided due to inconsistent evidence from previous studies. This new Norwegian study provides robust data that could change how potatoes are viewed in terms of health benefits.

The Norwegian study: Methodology and findings

The population-based prospective cohort study was conducted across three Norwegian counties – Northern, South-Western, and Central Norway. It involved 77,297 adults aged 18 to 64 who participated in cardiovascular health screenings between 1974 and 1988. Dietary information was collected using semi-quantitative food frequency questionnaires, which helped calculate weekly potato intake and daily cumulative mean intake.

Participants’ health status, lifestyle factors, and mortality data were also collected and analysed. These factors included smoking habits, physical activity levels, and education, providing a comprehensive view of each participant’s health and lifestyle. Over a mean follow-up period of 33.5 years, 27,848 deaths were reported among the participants, with 9,072 attributed to cardiovascular diseases.

The study revealed that participants who consumed 14 or more potatoes each week had a significantly lower risk of all-cause mortality compared to those who ate six or fewer potatoes weekly. Furthermore, each 100-gram daily increment in potato intake was associated with a 4% reduced risk of all-cause and cardiovascular disease-specific mortality.

Potatoes and cardiovascular health

One of the most intriguing aspects of the study is the specific impact of potato consumption on cardiovascular health. Among the deaths recorded, 4,620 were due to ischemic heart disease, and 3,207 were from acute myocardial infarction. The data showed a marginally inverse association between potato intake and the risk of death from these conditions. This means that higher potato consumption is linked to a slightly lower risk of dying from these heart-related conditions.

Men, in particular, seemed to benefit more from higher potato intake in terms of cardiovascular disease-specific mortality risk. The study suggests that the beneficial effects of potatoes are due to their nutrient content, which includes potassium, dietary fibre, and vitamin C. These nutrients are known to have positive effects on heart health, such as lowering blood pressure and improving vascular function.

Potassium, for instance, helps maintain electrolyte balance and proper muscle function, including the heart muscle. Dietary fibre aids in reducing cholesterol levels, which can prevent plaque buildup in arteries, thereby reducing the risk of heart disease. Vitamin C, an antioxidant, helps protect the heart by preventing oxidative damage to cells.

The role of preparation methods

The method of potato preparation plays a crucial role in determining their health impact. The study primarily focused on boiled potatoes, which are a common part of the Norwegian diet. Boiled potatoes are considered a high-quality carbohydrate source with a lower glycemic index compared to other forms like fried or mashed potatoes.’

Previous studies have often grouped all forms of potato consumption together, which might have skewed the results. For instance, fried potatoes and processed potato products have been associated with adverse health outcomes, while boiled potatoes are linked to beneficial effects. This distinction highlights the importance of considering preparation methods when evaluating the health benefits of potatoes.

Boiling potatoes preserve most of their nutrients and do not add extra fats or calories, unlike frying, which can introduce unhealthy fats and increase calorie content. This makes boiled potatoes a healthier option and a good source of energy and essential nutrients without the added health risks associated with other cooking methods.

Broader implications and future research

The findings of this study have significant implications for dietary guidelines and public health recommendations. Potatoes, especially when boiled, can be a valuable part of a healthy diet, contributing to reduced mortality and improved cardiovascular health. However, the study also notes that its findings are based on the Norwegian population and diet patterns from the 1970s and 1980s. This context might limit the generalizability of the results to other populations with different dietary habits.

Further research is needed to explore the impact of potatoes in diverse dietary contexts and to understand the long-term health effects of different preparation methods. Future studies should also consider the role of processed potato products separately from whole potatoes to provide more nuanced dietary guidelines.

One area of interest for future research is the potential health benefits of different potato varieties. For example, sweet potatoes and purple potatoes have been noted for their higher antioxidant content, which could offer additional health benefits. Understanding how different types of potatoes affect health could help refine dietary recommendations and encourage the inclusion of a variety of potatoes in diets.

The Norwegian study offers compelling evidence that potatoes, often underrated in nutritional discussions, can play a significant role in reducing the risk of cardiovascular disease and overall mortality. By focusing on boiled potatoes, the study provides a clearer picture of how this staple food can be part of a healthy diet. As dietary guidelines evolve, incorporating these findings could help promote better health outcomes and potentially extend life expectancy.

Potatoes are not just a comfort food; they are a nutritional powerhouse that can be a valuable addition to a heart-healthy diet. With their rich nutrient content and versatile preparation options, potatoes deserve a place in our daily meals. As the evidence continues to grow, it becomes increasingly clear that potatoes can contribute significantly to a healthy, balanced diet, supporting both longevity and overall well-being.

The study findings were published in the peer-reviewed journal: The Journal of Nutrition.