Which Starch is Lowest in Calories? The Resistant Starch Answer

November 20, 2025 •

4 min read

According to nutrition science, resistant starch provides significantly fewer calories per gram than regular digestible starch—about 2.5 kcal/g compared to 4 kcal/g. Understanding the calorie-saving power of resistant starch is crucial for anyone looking to incorporate lower-calorie starchy foods into their diet for better health and weight management.

Quick Summary

The lowest-calorie starches are those with a high content of resistant starch, a fiber-like carbohydrate that passes through the body undigested. Cooking and cooling starchy foods like potatoes and rice increases this component, providing fewer absorbable calories and promoting gut health.

Key Points

Resistant Starch is Key: Starches highest in resistant starch are lowest in calories, containing about 2.5 kcal/g compared to the 4 kcal/g of regular starch.
Cook and Cool Strategy: Cooking and then refrigerating foods like potatoes, rice, and pasta increases their resistant starch content through a process called retrogradation, lowering their calorie count.
Top Whole Food Sources: Excellent sources of low-calorie starches include legumes (lentils, chickpeas), oats, and starchy vegetables (butternut squash, beets).
Unripe is Better: Green, unripe bananas are a potent natural source of resistant starch, with content decreasing as they ripen.
Water and Fiber Matter: High water and fiber content in whole starchy foods significantly reduces their overall calorie density, making them more filling and beneficial.
Not All Flours Are Equal: While some pure starches like arrowroot and tapioca are calorically dense as powders, they are used minimally as thickeners. Certain modified starches are engineered to be low-calorie additives.

The Science Behind Low-Calorie Starches

Most people think of starches as high-calorie foods. While regular, easily digestible starches do contain about 4 calories per gram, a special type known as resistant starch functions differently in the body. Resistant starch is a form of carbohydrate that, as its name suggests, 'resists' digestion in the small intestine. Instead of being broken down into glucose and absorbed for energy, it travels to the large intestine where it is fermented by beneficial gut bacteria. This fermentation process creates short-chain fatty acids, which provide a smaller amount of energy, making the overall calorie load of the food lower. This biological trick is the primary reason some starchy foods can be considered lower in calories than others.

Natural Sources of Resistant Starch

Fortunately, nature provides several excellent, whole-food sources of resistant starch. Incorporating these into your diet can be a delicious way to enjoy carbs while managing your caloric intake. Legumes are particularly potent sources of both resistant starch and fiber, which also contributes to feelings of fullness and reduced calorie consumption.

Lentils and Beans: A cup of cooked lentils or black beans is not only rich in fiber and protein but also contains a healthy dose of resistant starch.
Oats: Especially steel-cut or rolled oats, these contain beta-glucan, a soluble fiber that acts as a type of resistant starch and is excellent for stabilizing blood sugar.
Unripe Bananas: Green, unripe bananas are one of the best natural sources of resistant starch, though the content decreases as the fruit ripens.

The Cool-Down Method: Maximizing Resistant Starch

A truly fascinating aspect of resistant starch is that its content can be manipulated through cooking and cooling. A process called retrogradation occurs when starchy foods are cooked and then refrigerated. This transforms some of the digestible starch into resistant starch, effectively lowering the food's total available calories.

How to Create Resistant Starch in Your Kitchen

Potatoes: Cook potatoes (boiling or baking is best), and then let them cool completely in the refrigerator before eating or using them for a dish like potato salad. Studies show this significantly increases their resistant starch content.
Rice: The same principle applies to rice. Cook it, cool it in the fridge, and then use it for a cold rice salad. Reheating the cooled rice is possible without completely reversing the resistant starch effect.
Pasta: Cooking and cooling pasta can also increase its resistant starch content, making chilled pasta salads a smart choice for calorie-conscious diners.

Comparison of Low-Calorie Starch Sources

To help illustrate the difference in calorie density, here is a comparison of various starchy foods, measured per 100 grams of the cooked product.


Food (Cooked, per 100g)	Approx. Calories	Primary Starch Type	Notes
Butternut Squash	40 kcal	Digestible Starch	High water content lowers density.
Beets	44 kcal	Digestible Starch	High water content, lower overall calories.
Green Peas	69 kcal	Digestible & Resistant	A good source of natural fiber.
Potatoes (Boiled & Cooled)	~70 kcal	High Resistant Starch	Resistant starch is created upon cooling.
Oats (Steel-Cut)	71 kcal	Digestible & Resistant	Excellent source of fiber and beta-glucan.
Chickpeas	88 kcal	Resistant & Digestible	A balance of protein, fiber, and resistant starch.
Brown Rice (Cooked & Cooled)	~129 kcal	High Resistant Starch	Cooling enhances the resistant starch effect.
Lentils	165 kcal	Resistant & Digestible	Nutrient-dense and high in protein and fiber.

Navigating Processed Starches and Flours

When it comes to pure starch powders, the picture is more complex. Modified starches used as food additives, such as Fibersym, are intentionally engineered to act as dietary fiber, providing significantly fewer calories (around 0.4 kcal/g). Arrowroot starch and tapioca starch, while gluten-free, are calorically dense as dry powders (over 350 kcal/100g). However, because they are used in very small quantities as thickeners, their overall calorie contribution to a meal is minimal. It’s important to distinguish between using a pure starch powder in small amounts and consuming whole starchy foods, where fiber and water content play a large role in lowering the overall calorie density per serving.

Conclusion: Making Smart Starch Choices for Your Diet

For those seeking to include the lowest-calorie starches in their diet, focusing on whole, unprocessed options is the best strategy. Prioritize legumes, oats, and starchy vegetables with high water and fiber content. To further reduce the available calories from starches like potatoes, rice, and pasta, simply cook and cool them before eating. This practical approach harnesses the power of resistant starch for weight management, improved gut health, and better blood sugar control, proving that smart cooking can make a big difference in the nutritional profile of your favorite foods. Focusing on these whole-food strategies is far more beneficial than trying to use processed flours as a main food source.

An excellent resource for learning more about whole-food nutrition is provided by Dr. McDougall, which highlights the benefits of focusing on caloric density in your diet.(https://www.drmcdougall.com/education/nutrition/the-calorie-density-approach-to-nutrition-and-lifelong-weight-management/)

Frequently Asked Questions

Resistant starch is a type of carbohydrate that is not digested in the small intestine. Instead, it moves to the large intestine where it is fermented by gut bacteria, yielding less energy for the body. This is why it provides only about 2.5 calories per gram compared to the typical 4 calories per gram of other starches.

Yes, cooling cooked potatoes significantly increases their resistant starch content. This process, known as retrogradation, means fewer calories are absorbed by your body. It's a great way to make potato salad a healthier option.

Whole grains are excellent sources of dietary fiber and other nutrients, which can increase satiety and promote better health. While some, like oats, are naturally higher in resistant starch, the overall calorie density is also influenced by other factors and how they are prepared.

As a pure, dried powder, tapioca starch is calorically dense. However, its 'low-calorie' reputation comes from its use as a thickening agent in small quantities, where its overall contribution to the dish is minimal. For pure consumption, it is not a low-calorie starch.

To maximize resistant starch, focus on cooking and cooling foods like potatoes, rice, and pasta. Include plenty of legumes and oats in your meals, and consider adding unripe green bananas to smoothies or snacks.

Starchy vegetables like butternut squash and beets have a high water content. This high water-to-starch ratio lowers their overall calorie density per serving, making them a more filling, nutrient-dense choice compared to more concentrated starches.

Yes, you can reheat foods like rice and potatoes that have been cooled to form resistant starch. While some resistant starch may convert back to digestible starch, a significant portion often remains, so you can still enjoy the benefits.