What are the disadvantages of eating potatoes?: A closer look at nutritional risks

October 29, 2025 •

4 min read

According to the Food and Drug Administration, acrylamide, a chemical formed when starchy foods like potatoes are cooked at high temperatures, is a potential carcinogen in animal studies. This highlights a key question in nutrition: What are the disadvantages of eating potatoes, and how do preparation methods and portion sizes truly affect our health?

Quick Summary

This article explores the nutritional downsides of potato consumption, including the risks of high glycemic index, the formation of potentially toxic acrylamides during high-heat cooking, and the presence of harmful solanine in green or sprouted potatoes. It also addresses the impact of high-fat preparations on weight and discusses potential digestive issues and nutrient imbalances. The key to mitigating these disadvantages lies in mindful preparation and moderation.

Key Points

Acrylamide Risk: High-temperature cooking like frying and roasting can create acrylamide, a potential carcinogen, making boiled or steamed potatoes a safer alternative.
Blood Sugar Spikes: Potatoes have a high glycemic index, which can cause rapid blood sugar increases, posing a risk for people with diabetes.
Solanine Poisoning: Green or sprouting potatoes contain toxic solanine, and cooking does not remove it, necessitating careful storage and avoidance of affected tubers.
Unhealthy Preparations: The biggest health risks come from high-calorie, high-fat preparations like French fries and chips, which contribute significantly to weight gain and poor health outcomes.
Nutrient Imbalance: Over-reliance on potatoes can displace more nutrient-dense vegetables and lead to dietary deficiencies, requiring a balanced, varied diet.
Digestive Distress: Some people may experience gas and bloating from the resistant starches in potatoes, especially when eaten raw or in large amounts.

The Problem with Preparation: Acrylamide and High-Fat Cooking

One of the most significant nutritional drawbacks of potatoes stems not from the vegetable itself, but from how it is prepared. Cooking methods that involve high heat, such as frying, roasting, or baking, can trigger the formation of acrylamide. This chemical is created during the Maillard reaction, a process that gives fried and baked foods their brown color and characteristic flavor.

Acrylamide is classified as a potential human carcinogen based on animal studies.
French fries and potato chips, due to deep-frying and high-temperature processing, tend to have the highest levels of this compound.
Avoiding high-heat methods and opting for boiling or steaming can eliminate the risk of acrylamide formation.

Beyond acrylamide, high-fat cooking methods add substantial calories and unhealthy fats. For example, a study showed that one daily serving of French fries was associated with a significant average weight gain over four years. Toppings often added to potatoes, like butter, cheese, and sour cream, further increase the calorie and saturated fat content, contributing to weight gain and heart disease risk, especially for those with diabetes.

Glycemic Index and Blood Sugar Concerns

Potatoes have a relatively high glycemic index (GI), a measure of how quickly a food raises blood sugar levels. Starchy potato varieties like Russets and methods like baking can lead to rapid spikes in blood glucose. This is particularly problematic for individuals with diabetes or those at risk of developing type 2 diabetes.

Studies have indicated that higher intakes of potatoes are associated with an increased risk of type 2 diabetes, with fried potatoes contributing the most significant risk.
The rapid blood sugar spike can be followed by a crash, leading to increased hunger and potentially overeating.

However, it is important to note that the GI is not the only factor. Eating potatoes with protein, fiber, and healthy fats can help slow the digestion of carbohydrates and moderate the blood sugar response. A surprising tip is that cooling cooked potatoes before eating, as in a potato salad, increases their resistant starch content, which has a prebiotic effect and a lower glycemic load.

Toxic Threats: Solanine in Green or Sprouted Potatoes

Potatoes are part of the nightshade family and naturally contain glycoalkaloids, including solanine. This compound serves as a natural defense mechanism against pests but can be toxic to humans in high concentrations. Solanine levels increase when potatoes are exposed to sunlight, causing them to turn green, or when they begin to sprout.

Consuming high doses of solanine can lead to acute poisoning, with symptoms ranging from mild digestive upset (nausea, diarrhea, vomiting) to more severe neurological effects.
Cooking does not effectively destroy solanine.
To avoid this risk, it is crucial to discard potatoes that have extensive greening, appear shrunken, or have sprouts. Removing small green patches might suffice, but if the potato tastes bitter, it should be thrown out.

Nutrient Imbalance and Displacement

While potatoes offer valuable nutrients like potassium and vitamin C, they are not a complete source of nutrition. Relying heavily on potatoes in the diet can lead to a nutrient imbalance, especially if they displace other, more nutrient-dense vegetables.

Potatoes are lower in essential nutrients like protein, healthy fats, and certain vitamins (e.g., A, E, K) compared to low-calorie vegetables like leafy greens or broccoli.
A diet composed mostly of potatoes lacks the essential fatty acids needed for brain and heart function.
A varied diet rich in different vegetables and food groups is essential for obtaining all necessary vitamins and minerals.

Digestive Issues and Allergies

Some individuals may experience digestive discomfort from potatoes, especially when consuming them raw or in large quantities. Raw potatoes are high in resistant starch, which can ferment in the gut, causing gas, bloating, and cramps for sensitive individuals. Additionally, some people have a rare allergy to potatoes, specifically to the protein patatin, which can cause symptoms like rhinitis, skin irritation, or digestive issues.

Comparison of Healthy vs. Unhealthy Potato Preparation


Feature	Healthy Preparation	Unhealthy Preparation
Cooking Method	Boiling, steaming, cooling	Frying, deep-frying, over-baking
Health Impact	Retains nutrients, no added fats or calories, increased resistant starch.	High in unhealthy fats and calories, potential for harmful acrylamides.
Glycemic Index	Lower GI, especially when cooled.	Higher GI, leading to blood sugar spikes.
Toxin Risk	Minimal risk, assuming proper storage and preparation.	Risk of solanine if green or sprouted parts are not removed.
Associated Weight	Can be part of a weight-management plan when portion-controlled and prepared healthily.	Increased risk of weight gain due to high fat and calorie additions.

Conclusion

While potatoes have a place in a balanced diet due to their nutritional benefits, the disadvantages of eating potatoes are primarily linked to preparation methods and portion control. Frying and high-temperature cooking can introduce potential health risks like acrylamide, while improper storage can lead to toxic solanine buildup. For individuals managing blood sugar or weight, the high glycemic index of certain preparations warrants caution. The key to enjoying potatoes without compromising health is moderation, choosing healthier cooking methods like boiling or steaming, and being mindful of food combinations. Making informed choices ensures this versatile staple remains a healthy component of your nutritional plan.

Mayo Clinic Health System: It's OK to say 'yes' to potatoes

Frequently Asked Questions

No, it is not inherently unhealthy to eat potatoes daily, provided they are prepared healthily (boiled, steamed) and consumed in moderation as part of a balanced diet that includes a variety of other vegetables.

Fried potatoes carry a higher health risk due to the formation of potential carcinogens like acrylamide during high-heat cooking and the addition of unhealthy fats and calories.

Solanine poisoning is a condition caused by ingesting high levels of the toxic glycoalkaloid solanine, found in green or sprouted potatoes. Symptoms include digestive and neurological issues.

Yes, people with diabetes can eat potatoes, but they should be mindful of portion sizes and choose preparations that lower the glycemic impact, such as boiling and cooling, and pairing them with protein and fiber.

Potatoes themselves do not automatically cause weight gain. It is the high-fat, high-calorie cooking methods and toppings, as seen with French fries and chips, that significantly contribute to weight gain.

Eating a potato with extensive green coloring is not recommended due to high levels of solanine, which can cause poisoning. Any potato that tastes bitter should also be discarded.

You can reduce the glycemic index by cooking and then cooling potatoes, which increases their resistant starch content. Eating them alongside protein, fat, and fiber also helps moderate blood sugar impact.