HYPE: Air frying cuts oil, calories and harmful cooking compounds.
But what does the evidence actually show?
Air frying can reduce absorbed oil and energy compared with deep frying of similar foods. It does not consistently reduce every cooking contaminant, make every food healthy or demonstrate long-term disease prevention.
The hype
Air fryers promise the familiar texture of fried food with much less oil. The strongest version of the claim is practical: can replacing a deep-fried serving with a comparable air-fried serving reduce the fat and energy you eat? The much broader promise is that the appliance automatically makes a meal healthy and removes harmful compounds. Those claims need different evidence.
The claim: why people believe this
A domestic air fryer is a compact hot-air oven. Deep frying surrounds food with hot oil; air frying uses circulating heat with a smaller amount of added oil. That gives a sound reason to expect less oil uptake under suitable conditions. It does not mean the resulting meal is oil-free, especially when the starting product was already fried or contains added fat.
The comparator matters. A difference from deep frying is not automatically an advantage over steaming, boiling or a conventional oven using the same ingredients and oil amount.
What does the evidence show?
The most direct evidence concerns food composition and processing chemistry. These experiments can measure oil and contaminants well, but they do not measure a person’s weight, heart-disease risk or lifespan.
Less fat, with a food-specific energy difference
Santos and colleagues compared potatoes cooked in air-frying equipment and by deep frying with different vegetable oils. Air-fried potatoes averaged about 70% less fat and about 45 fewer kcal per 100 g. Most assessed chemical measures, including acrylamide, were similar. Those values describe the tested potatoes and protocols, not every food or a universal appliance claim.
Read the research ↗Optimisation can improve several measured properties
A study of air-jet-impingement-assisted air frying compared frozen fries and wedges with deep frying and convection cooking. Under selected conditions, the prototype reduced oil uptake and lipid oxidation and suppressed acrylamide. Temperature, airflow and time all influenced results. This specialised system and its optimised settings cannot stand in for every domestic air fryer.
Read the research ↗Acrylamide: less oil does not mean less of every contaminant
Acrylamide can form when starchy foods are cooked at high temperatures. It arises during several methods, including frying, baking and roasting; reducing the oil alone does not remove that chemistry. UK food-safety guidance recommends reducing exposure as a precaution based on the evidence, including animal cancer findings. That is not proof that an occasional air-fried meal causes cancer. [5]
The air-fried samples were not significantly better
Navruz-Varlı and Mortaş compared washing or soaking and three cooking methods. Acrylamide was numerically highest in the air-fried potatoes, but differences between cooking methods were not statistically significant. This cannot establish that air frying is more dangerous. It does demonstrate why the method cannot simply be advertised as consistently lowering acrylamide.
Read the research ↗Preparation changed the comparison
Esposito and colleagues tested air, microwave and deep frying with or without asparaginase pretreatment. Without pretreatment, the air-fried samples had the highest measured acrylamide. Enzyme treatment changed levels substantially. This laboratory result is relevant to processing chemistry, not a reason to copy industrial pretreatments at home or predict a consumer’s cancer risk.
Read the research ↗Why the results differ
The studies use different potato preparations, equipment, temperatures, cooking times and end points. Comparing a lightly cooked sample with a darker, longer-cooked one can change the answer. The 2026 prototype’s promising result and the other studies’ less favourable comparisons can both be true under their respective conditions.
Lipid oxidation is similarly conditional. The 2017 study found more damaged incorporated fat after deep frying, but also differences between its air-frying machines. A laboratory oxidation measure cannot be converted directly into a demonstrated reduction in human disease. [1]
What about nutrient retention?
There is no single nutrient-retention score that makes one appliance best. The 2017 study found somewhat better ascorbic-acid results with air frying in its potato comparison. Other nutrients, foods and cooking conditions need their own comparisons. Lower total fat also changes the composition; it does not automatically increase every desirable nutrient. [1]
The catch: a lower-energy serving is not a clinical trial
If a substitution really lowers energy intake without later compensation, it can contribute to an energy-reduced diet. Eating larger portions, adding sauces or changing the rest of the diet can offset that difference. This is a practical inference from composition, not a measured weight-loss effect of owning an air fryer.
The studies reviewed here do not establish that switching appliances prevents heart attacks, cancer or other long-term disease. A packaged food also retains its ingredients, salt and existing fat when air-fried. Cooking method is one part of nutritional quality.
What this means for you
An air fryer can be a useful way to cook foods you enjoy with less added oil than deep frying. Measure the oil you add if the aim is to reduce it, and compare like-for-like portions. Consider vegetables, protein foods and the whole meal alongside the cooking method.
For starchy foods, aim for golden yellow or lighter rather than very dark browning, and follow the packet and appliance instructions. UK guidance no longer gives a blanket instruction never to refrigerate raw potatoes at home, so old social-media lists may be out of date. [5]
There is no need to buy a particular appliance to improve your diet. A conventional oven and suitable cooking habits may meet the same practical need. See the separate ultra-processed-food investigation for what whole-diet trials show.
A useful lower-oil alternative to deep frying. Food choice, preparation and browning still matter, and long-term health promises remain unproven.
Research & Sources
1. Santos et al. (2017). Deep or air frying? A comparative study with different vegetable oils. European Journal of Lipid Science and Technology.
Read the original source ↗2. Air Jet Impingement-Assisted Air Frying of Potatoes: Oil Absorption, Lipid Oxidation and Acrylamide Formation for Improved Nutritional Quality (2026). Food Science & Nutrition.
Read the original source ↗3. Navruz-Varlı & Mortaş (2024). Acrylamide formation in air-fried versus deep and oven-fried potatoes. Frontiers in Nutrition.
Read the original source ↗4. Esposito et al. (2025). Evaluation of the effect of enzymatic pretreatment with l-asparaginase on acrylamide formation during microwave, air, and deep frying of potatoes. Journal of Food Science.
Read the original source ↗5. UK government / Food Standards Agency. Acrylamide: formation, precautionary advice and home-cooking guidance. Current page checked October 2026.
Read the original source ↗Evidence reviewed: October 2026
This targeted editorial review assessed research available on 13 October 2026; it is not an exhaustive systematic review. Sources were checked against published research records and full text where accessible. Abstract-only assessments are identified. Evidence vs Hype provides education, not individual diagnosis or treatment. Featured artwork is conceptual, not a study result. No commercial product was selected or endorsed for this investigation.