Why Are Sweet Potato Fries Unhealthy? The Full Nutritional Truth

November 25, 2025 •

3 min read

Deep-fried sweet potato fries can contain more calories and fat per serving than regular potato fries, with some restaurant versions exceeding 400 calories. This eye-opening reality challenges the perception that sweet potato fries are a guilt-free side dish, revealing why they can be unhealthy depending on preparation.

Quick Summary

Deep-fried sweet potato fries are high in calories, unhealthy fats, and potentially harmful acrylamide due to the cooking method. Preparation, portion sizes, and added salt are the main factors that impact their nutritional value, despite the inherent benefits of the raw sweet potato.

Key Points

Deep-Frying Adds Excess Fat: The process of deep-frying causes sweet potato fries to absorb a large amount of oil, significantly increasing calories and fat content.
Potential for Acrylamide Formation: High-temperature cooking, especially deep-frying, can lead to the formation of acrylamide, a chemical linked to cancer risk in animal studies.
Hidden Calories from Restaurant Portions: Many restaurant-sized servings are oversized and come with high-calorie dips, leading to easy overconsumption and weight gain.
Frying Negates Glycemic Index Benefits: While raw sweet potatoes have a lower glycemic index, frying and high-temperature baking can cause blood sugar spikes similar to regular fries.
Baking is a Healthier Alternative: To enjoy the nutritional benefits of sweet potatoes, opt for baking or air-frying them at home with minimal, healthier oils like olive oil.

The Deceptive Cooking Method: Deep-Frying

The most significant factor compromising the health benefits of sweet potato fries is the deep-frying process. While raw sweet potatoes offer nutrients like vitamins A and C, fiber, and antioxidants, frying causes them to absorb substantial fat, dramatically increasing caloric density. Deep-fried sweet potato fries can equal a meal's calories.

The Problem with Reused Frying Oil

Restaurant frying often uses reheated oil, which can break down and form trans fats. These unhealthy fats negatively impact cholesterol levels (raising LDL, lowering HDL) and are linked to increased risk of heart disease.

The Formation of Acrylamide: A Potential Health Risk

Acrylamide is a chemical formed in starchy foods like potatoes when cooked at high temperatures (over 120°C) during the browning (Maillard) reaction. Both sweet and regular potato fries can contain acrylamide, a potential carcinogen in animal studies. Deep-frying's intense heat and longer cooking times increase acrylamide formation. The FDA monitors acrylamide due to its potential health effects. Learn more from the FDA here.

Caloric Density and Portion Control Issues

Though raw sweet and white potatoes have similar calories, deep-frying significantly increases both calories and fat, potentially doubling them compared to baking. Restaurant portions are often large, making it easy to consume excessive calories and hinder weight management.

The Glycemic Index Myth

While raw sweet potatoes typically have a lower glycemic index (GI), frying or even high-temperature baking can alter starches, leading to a blood sugar rise similar to regular fries. The low fiber in the finished product also reduces the GI benefit.

Other Health Concerns Associated with Fried Sweet Potato Fries

Additional factors contribute to the unhealthiness of deep-fried sweet potato fries:

High Sodium Content: Added salt in restaurant and frozen versions can lead to excessive sodium intake, impacting blood pressure.
High-Calorie Dips and Sauces: Accompaniments often add significant calories, sugar, and fat.
Nutrient Loss: High frying temperatures can reduce heat-sensitive nutrients like vitamin C.

Comparing Sweet Potato Fries: Baked vs. Deep-Fried


Feature	Baked Sweet Potato Fries	Deep-Fried Sweet Potato Fries
Calories	Significantly lower	Significantly higher
Fat Content	Minimal, from heart-healthy oil	Very high, from absorbed frying oil
Nutrient Retention	High retention of vitamins and fiber	Potential loss of heat-sensitive nutrients
Acrylamide Risk	Present but manageable with careful cooking	Higher risk due to intense heat and longer exposure
Overall Health Impact	Healthier choice, better for weight management	Less healthy, contributes to weight gain and disease risk

Healthy Preparation Methods

Healthier options for enjoying sweet potatoes include:

Baking: Toss wedges or sticks with a little olive oil and bake until crispy.
Air-Frying: Achieves crispiness with significantly less oil than deep-frying.
Steaming or Boiling: Preserves nutrients without added fat.
Mashed or Roasted: Enjoy as a nutrient-rich side dish.

Conclusion: Moderation and Preparation are Paramount

The idea that sweet potato fries are inherently healthy is a misconception often based on the raw vegetable's nutritional value. Deep-frying adds unhealthy fats, increases calories, and creates potential carcinogens like acrylamide. While homemade baked or air-fried versions can be nutritious, restaurant and frozen options are often unhealthy. Enjoying sweet potatoes healthily requires moderation and choosing preparation methods like baking or air-frying, while being mindful of portion sizes and toppings.

Frequently Asked Questions

Not necessarily. While raw sweet potatoes are more nutrient-dense than white potatoes, deep-frying makes both types of fries similarly high in calories, fat, and potentially harmful compounds like acrylamide.

Acrylamide is a chemical that can form in starchy foods cooked at high temperatures. It forms naturally during the browning process (Maillard reaction) when sugars and the amino acid asparagine react. The risk of acrylamide formation increases with the high heat and longer cooking times used in frying.

The easiest way is to bake or air-fry them at home instead of deep-frying. This requires less oil and helps preserve more of the sweet potato's nutrients.

Acrylamide levels in frozen sweet potato fries can vary depending on the manufacturer and cooking instructions. Freezing and processing techniques are used to mitigate acrylamide, but high-temperature cooking at home can still contribute to its formation.

Yes. While raw sweet potatoes have a lower glycemic index, high-temperature cooking like frying alters their starch structure, causing a sharper spike in blood sugar levels, similar to regular french fries.

In their unprocessed, baked form, sweet potatoes generally have more fiber and are significantly richer in vitamin A than white potatoes. However, both are nutritious vegetables, and the cooking method is more critical for overall health.

For maximum health benefits, eat them boiled, roasted, or steamed. These methods retain nutrients and avoid adding excess fats and potentially harmful compounds that can form during high-temperature frying.