Frying food can increase the number of calories you consume. Additionally, frying with certain types of oils may pose health risks.

Deep frying is a common cooking method used across the globe. Restaurants and fast-food chains often use it as a quick and inexpensive way to prepare foods.

Popular fried foods include fish, french fries, chicken strips, and cheese sticks, although you can deep-fry just about anything.

Many people like the taste of fried foods. But these foods tend to be high in calories and trans fat, so eating a lot of them can negatively affect your health.

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Compared to other cooking methods, deep frying adds a lot of calories.

Fried foods are typically coated in batter or flour before being fried. And when foods are fried in oil, they lose water and absorb fat, which further increases their calorie content (1).

Generally speaking, fried foods are significantly higher in fat and calories than their non-fried counterparts.

For example, one small baked potato (138 grams [g]) contains 128 calories and 0.18 g of fat, while the same amount (138 g) of french fries contains 431 calories and 20 g of fat (2, 3).

As another example, a 100-g fillet of baked cod contains 105 calories and 1 g of fat, while the same amount of deep-fried fish contains 200 calories and 10 g of fat (4, 5).

As you can see, calories add up quickly when eating fried foods.


Fried foods contain more calories than their non-fried counterparts. Eating a lot of them can significantly increase your calorie intake.

Trans fats form when unsaturated fats undergo a process called hydrogenation.

Food manufacturers often hydrogenate fats using high pressure and hydrogen gas to increase their shelf life and stability, but hydrogenation also occurs when oils are heated to very high temperatures during cooking.

The process changes the chemical structure of fats, making them difficult for your body to break down, which can ultimately lead to negative health effects.

In fact, trans fats are associated with an increased risk of many health conditions, including heart disease, cancer, diabetes, and obesity (6, 7, 8).

Since fried foods are cooked in oil at extremely high temperatures, they are likely to contain trans fats.

What’s more, fried foods are often cooked in processed vegetable or seed oils, which may contain trans fats before heating.

When these oils are heated to high temperatures, such as during frying, their trans fat content can increase (9).

In fact, one study found that each time an oil is reused for frying, its trans fat content increases (10).

However, it’s important to distinguish between these artificial trans fats and trans fats that occur naturally in foods such as meat and dairy products.

These have not been shown to have the same negative health effects as those found in fried and processed foods.


Fried foods are often cooked in processed vegetable or seed oils. When heated, these oils can form trans fats, which are associated with a number of health problems, including an increased risk of several diseases.

Several studies in adults have found an association between eating fried foods and the risk of chronic disease.

Generally speaking, eating more fried foods is associated with a greater risk of developing type 2 diabetes, heart disease, and obesity (11).

Heart disease

Eating fried foods may contribute to high blood pressure, low HDL (“good”) cholesterol, and obesity, all of which are risk factors for heart disease (12, 13, 14).

In fact, two large, older observational studies found that the more often people ate fried foods, the greater their risk of developing heart disease was (15).

One 4-year study with 16,479 participants concluded that eating 2 servings of fried fish per week is associated with a higher risk of cardiovascular disease (16).

Meanwhile, those who ate a diet high in fruits and vegetables had a significantly lower risk.


Several older studies have found that eating fried foods increases the risk of developing type 2 diabetes (17, 18).

A 2005 study found that people who ate fast food more than twice per week were twice as likely to develop insulin resistance as those who ate it less than once per week (19).

Furthermore, in 2014, two large observational studies found a strong association between how often participants ate fried food and their risk of type 2 diabetes.

Those consuming 4–6 servings of fried food per week were 39% more likely to develop type 2 diabetes than those consuming less than 1 serving per week.

Similarly, those who ate fried food 7 or more times per week were 55% more likely to develop type 2 diabetes than those who ate less than 1 serving per week (15).


Fried foods contain more calories than their non-fried counterparts, so eating a lot of them can significantly increase your calorie intake. This can contribute to weight gain.

Furthermore, studies indicate that the trans fats in fried foods may play a significant role in weight gain, as they can affect the hormones that regulate appetite and fat storage (20).

Regardless of whether it’s due to high calorie content or high trans fat content, multiple observational studies have shown a positive association between fried food intake and obesity (14, 21).


Individuals who regularly consume fried foods may be at a higher risk of developing type 2 diabetes, heart disease, and obesity. It seems that the greater your intake is, the greater your risk will be.

Acrylamide is a toxic substance that can form in foods during high temperature cooking such as frying, roasting, or baking.

It is formed by a chemical reaction between sugars and an amino acid called asparagine.

Starchy foods such as fried potato products and baked goods typically have higher concentrations of acrylamide (22).

An older animal study suggests that it poses a risk for several types of cancer (23).

However, most of these earlier studies used very high doses of acrylamide, 1,000–100,000 times the average amount that humans would be exposed to through diet (24).

While a handful of human studies have investigated acrylamide intake, the evidence is mixed.

One review found a modest association between dietary acrylamide in humans and kidney, endometrial, and ovarian cancers (25).

Other studies indicate that dietary acrylamide in humans is not related to the risk of any common type of cancer (26).


Animal studies suggest that dietary intakes of acrylamide may increase the risk of several types of cancer, but more studies in humans are needed before researchers can say for sure.

If you enjoy the taste of fried foods, consider cooking them at home using healthier oils or alternative “frying” methods.

Healthy oils

The type of oil used for frying heavily influences the health risks associated with fried foods. Some oils can withstand much higher temperatures than others and are therefore safer to use.

Generally speaking, oils that consist mostly of saturated and monounsaturated fats are the most stable when heated.

Coconut, olive, and avocado oils are among the safest and most stable for frying:

  • Coconut oil: More than 90% of the fatty acids in coconut oil are saturated, which means this oil is very resistant to heat. In fact, studies have shown that even after 8 hours of continuous deep frying, its quality does not deteriorate (27).
  • Olive oil: Olive oil contains mostly monounsaturated fats, so it’s relatively stable for high temperature cooking (28).
  • Avocado oil: The composition of avocado oil is similar to that of olive oil. It also has an extremely high heat tolerance, which makes it a great choice for deep frying.

Using these healthier oils may decrease some of the risks associated with eating fried foods. But note that these are the most stable oils for frying, not necessarily the most nutritious ones in general.

Unhealthy oils

Cooking oils that contain large amounts of polyunsaturated fats are far less stable and are known to form acrylamide when exposed to high heat (29).

Examples include:

  • canola oil
  • soybean oil
  • cottonseed oil
  • corn oil
  • sesame oil
  • sunflower oil
  • safflower oil
  • grapeseed oil
  • rice bran oil

Restaurants commonly use these oils because they tend to be cheaper. But you should avoid these oils for deep frying at home.

Alternatives to traditional frying

You may also want to consider alternative cooking methods such as:

  • Oven-frying: This method involves baking foods at a very high temperature (450°F or 232°C), which allows foods to get crispy using little or no oil.
  • Air-frying: You can also “fry” foods in a hot air fryer. These machines work by circulating extremely hot air around food. The foods end up crispy on the outside and very moist on the inside, similar to traditionally fried foods, with the use of 70–80% less oil.

Coconut, olive, and avocado oils are among the most stable oils to fry foods in. You can also try oven-frying and air-frying, cooking methods that yield similar results while using very little oil.

Consuming foods fried in unstable oils can have several negative health effects.

In fact, eating them regularly can put you at a higher risk of developing diseases such as diabetes, heart disease, and obesity.

Therefore, it’s probably best to avoid or severely limit your intake of commercially fried foods.

There are several other cooking methods and healthier fats you can use instead.