Does Cooking Rice Decrease Calories? The Truth About Resistant Starch

December 29, 2025 •

4 min read

According to research presented at the American Chemical Society, a specific cooking method involving coconut oil and chilling can reduce rice calories by up to 60%. The initial cooked calorie count for a serving of rice does not decrease, but how your body processes it can be significantly altered to reduce net calorie absorption.

Quick Summary

The total calories in rice don't change during cooking, but a process involving adding fat and chilling increases resistant starch, making it less digestible. This reduces the number of calories the body can absorb from the rice.

Key Points

No Calorie Loss, But Less Absorption: Cooking rice doesn't decrease its total calories, but a specific method can significantly reduce the amount your body absorbs.
Resistant Starch is Key: Adding coconut oil and chilling cooked rice for 12+ hours converts some of the digestible starch into resistant starch, which is not broken down by the body.
Diluted Calories by Weight: The common misconception comes from comparing uncooked and cooked rice by weight; cooked rice is heavier due to water absorption, diluting its calorie density.
Reheating Maintains Effect: The resistant starch formed by chilling the rice is not lost when the rice is reheated.
Other Benefits Exist: This method can also improve gut health and lower the glycemic index of the rice, leading to a slower release of sugar into the bloodstream.
Manage Expectations: Early claims of extreme calorie reduction (50-60%) might be overstated; a more modest reduction (10-15%) is likely.

The Calorie Misconception: Uncooked vs. Cooked

Many people are confused about why calorie counts differ between cooked and uncooked rice. The raw fact is that the total caloric content of a batch of rice remains the same regardless of whether it's cooked or not. The confusion arises because rice absorbs water during the cooking process, causing its weight to increase significantly. A 100-gram portion of uncooked rice contains a certain number of calories, while a 100-gram portion of cooked rice contains fewer calories because it includes a large amount of zero-calorie water. When you measure by weight after cooking, you're measuring both the rice and the absorbed water, which dilutes the calorie density per gram. Therefore, for accurate tracking, it is recommended to weigh rice in its dry, uncooked form.

The Role of Resistant Starch

Recent studies have brought a fascinating nuance to this topic: while cooking alone doesn't reduce calories, a specific method can change the rice's structure to make some of its starch indigestible. This indigestible starch is known as 'resistant starch' (RS) because it 'resists' digestion in the small intestine, acting more like fiber than a carbohydrate. It is not absorbed as glucose and therefore does not contribute to the body's calorie count.

How to Create Resistant Starch in Rice

Creating resistant starch involves adding fat during cooking and then cooling the rice. Adding a fat like coconut oil to the boiling water before the rice helps protect the starch granules from digestive enzymes. Cooling the cooked rice for at least 12 hours in the refrigerator is crucial as it causes a process called 'retrogradation,' converting soluble starch into resistant starch.

The Impact of Reheating

Reheating the cooled rice does not reverse the resistant starch formation. While reheating is possible, proper food safety is important to prevent food poisoning from bacteria like Bacillus cereus. Always cool rice quickly and reheat until steaming hot, and only reheat once.

Cooking Methods Comparison

Different preparation methods affect rice's caloric impact.


Cooking Method	Preparation Details	Starch Profile	Calorie Absorption Impact	Best For
Standard Cooked	Cooked in water until done, served hot.	High in digestible starch.	Full calorie absorption.	Basic meals, where calorie reduction is not the priority.
Cooked and Cooled	Cooked in water, chilled for 12+ hours.	Increased resistant starch content.	Small calorie reduction (approx. 10-15%).	Improving glycemic response and adding gut health benefits.
RS Method (Oil + Chill)	Cooked with coconut oil, chilled for 12+ hours, then reheated.	Significantly increased resistant starch.	Potential significant calorie reduction (up to 50-60% reported in initial studies).	Calorie-conscious meals, weight management.

The Role of Different Rice Types

The resistant starch method has primarily focused on white rice, but brown rice may also benefit due to its higher fiber content. Studies are still preliminary, and some suggest the calorie reduction may be more modest than initially reported. The science of resistant starch formation also applies to other starchy foods like potatoes and pasta.

A Balanced Perspective on Calorie Reduction

Using the resistant starch method is one potential tool for managing rice calories, but it should complement a healthy diet. Claims of a 50-60% reduction are based on early studies and may be higher than realistic outcomes, with estimates around 10-15% being more likely. Effective weight management is better achieved through portion control and combining rice with vegetables and lean proteins.

Beyond Calories: Other Health Benefits

Resistant starch provides benefits beyond calorie reduction, acting as a prebiotic that supports beneficial gut bacteria. A healthy gut is linked to better digestion and overall health. Converting starch to RS can also lower the glycemic response, resulting in a slower release of glucose into the bloodstream, which helps manage blood sugar levels.

Conclusion

While cooking doesn't eliminate rice calories, specific techniques can increase resistant starch, reducing the calories your body absorbs. Adding a small amount of fat and chilling cooked rice makes starches less digestible. This scientific method, combined with balanced eating and portion control, can aid in weight management and improve gut health. Always consult a healthcare professional for personalized advice. A simple cooling step after cooking rice can offer nutritional benefits.

Simple Steps for Calorie Reduction

Select Your Rice: Any rice type can be used, though white rice is most studied.
Add Fat: Use one teaspoon of coconut oil per half cup of uncooked rice, added to boiling water.
Cook Normally: Cook the rice as usual.
Cool for 12 Hours: Refrigerate the cooked rice in a shallow container for at least 12 hours.
Reheat and Enjoy: Reheat thoroughly when ready. The resistant starch remains.

Frequently Asked Questions

No, the act of cooking rice does not destroy calories. The total calorie count of the original grains remains the same. Any perceived reduction per gram is due to the added weight of absorbed water.

You can reduce the number of calories your body absorbs by creating resistant starch. This involves cooking rice with a small amount of coconut oil and then refrigerating it for at least 12 hours before eating.

Resistant starch is a type of carbohydrate that is not digested in your small intestine. Your body cannot absorb its calories, so it essentially passes through the system like dietary fiber.

Yes, but with proper food safety precautions. Cool the rice rapidly after cooking and refrigerate it. When reheating, ensure it is steaming hot throughout and only reheat it once.

While the method has been researched primarily with white rice, the science of resistant starch formation applies to other starchy foods. It is expected to work on other rice types, though the precise calorie reduction may vary.

A small amount is sufficient. The research suggests adding one teaspoon of coconut oil for every half cup of uncooked rice.

Yes, a teaspoon of coconut oil contains about 39 calories. However, the calorie reduction from the resistant starch conversion is expected to outweigh this addition.