What are the macros for 40g of black beans? A Detailed Nutritional Breakdown

January 3, 2026 •

3 min read

A 40g serving of cooked black beans provides approximately 53 calories, along with a beneficial blend of plant-based protein, fiber, and complex carbohydrates. This makes even a small portion a nutritional powerhouse in any diet. Here is a detailed look at what are the macros for 40g of black beans, highlighting their significance for your health.

Quick Summary

A 40g serving of cooked black beans contains approximately 53 calories, with a macro breakdown of about 3.5g protein, 9.5g carbs, and negligible fat, plus fiber.

Key Points

Cooked vs. Raw: 40g of raw black beans contains significantly more calories and macros than 40g of cooked black beans due to water content.
Lean Protein Source: A 40g serving of cooked black beans offers a low-fat, plant-based protein boost of about 3.5g.
Fiber Rich: This small serving provides a notable amount of dietary fiber (approx. 3.5g), supporting digestive health and satiety.
Low Calorie: At around 53 calories per 40g cooked portion, black beans are an excellent low-calorie addition to meals.
Micronutrient Powerhouse: Beyond macros, black beans are packed with essential minerals like iron, folate, and manganese.

The Macronutrient Profile of 40g Cooked Black Beans

To understand the macros for 40g of black beans, it's crucial to specify whether they are cooked or raw, as the nutritional density changes significantly with water content. A standard 172g cup of cooked black beans provides 227 calories. Using this as a baseline, we can calculate the approximate macros for a 40g cooked serving:

Calories: Approximately 53 kcal (40/172 * 227). This makes it a very low-calorie addition to your meals, perfect for those monitoring their energy intake.
Carbohydrates: Approximately 9.5g (40/172 * 40.8g). These are primarily complex carbohydrates, which provide sustained energy and are important for overall health.
Fiber: Approximately 3.5g (40/172 * 15g). This high fiber content is excellent for digestive health, promoting regularity and helping you feel full longer.
Protein: Approximately 3.5g (40/172 * 15.2g). While a small amount, this contributes to your daily protein needs and is a valuable source for plant-based diets.
Fat: Approximately 0.2g (40/172 * 0.93g). Black beans are naturally very low in fat, with no saturated or trans fats, making them a heart-healthy choice.

Raw vs. Cooked Macros: A Comparison

The water absorption during cooking drastically alters the nutritional profile per gram. Here's a comparison to illustrate the difference based on search data.


Nutrient	40g Cooked Black Beans	40g Raw Black Beans
Calories	~53 kcal	136 kcal
Carbohydrates	~9.5g	25g
Protein	~3.5g	9g
Fat	~0.2g	1g
Fiber	~3.5g	6g

This comparison clearly shows that a 40g serving of dried, raw black beans is far more calorie-dense than the same weight of cooked beans. The cooked version is bulked up with water, diluting its nutritional density per gram.

Health Benefits of Black Beans

Beyond their basic macro components, black beans offer a wealth of health benefits that make them a valuable part of a balanced diet.

Excellent Source of Dietary Fiber: The high fiber content supports gut health, aids digestion, and helps regulate blood sugar levels.
Rich in Minerals: Black beans are a good source of essential minerals, including iron, potassium, magnesium, and phosphorus, all vital for bodily functions.
Antioxidant Powerhouse: The dark color of black beans comes from anthocyanins, powerful antioxidants that help combat cellular damage from free radicals. (This information can be found on many nutrition-related health sites)
Heart-Healthy: Being low in fat and free of cholesterol, black beans can help support cardiovascular health.
Promotes Satiety: The combination of fiber and protein helps you feel full and satisfied, which can be a key factor in weight management.

How to Incorporate 40g of Black Beans into Your Diet

Including a small, portion-controlled amount of black beans in your daily meals is simple and delicious. Here are a few ideas:

Salad Topping: Sprinkle 40g of cooked black beans over your favorite salad for a fiber and protein boost.
Rice Bowls: Add them to a grain bowl with rice, corn, and avocado for a complete meal.
Salsa Enhancement: Mix them into a fresh salsa with tomatoes, onions, and cilantro for extra texture and nutrition.
Quick Side Dish: Heat them with a little cumin and chili powder for a flavorful side dish.

Exploring Other Key Nutrients

While the macros are a great starting point, black beans are also rich in several key micronutrients:

Folate (Vitamin B9): Essential for cell growth and metabolism, black beans are a significant source of folate.
Manganese: A trace mineral important for many enzyme functions in the body.
Thiamin (Vitamin B1): Crucial for energy production and nerve function.
Iron: Black beans provide a plant-based source of iron, which is important for transporting oxygen in the blood.

Conclusion

A 40g serving of cooked black beans is a convenient and nutrient-dense addition to any meal. Offering around 53 calories, it provides a valuable mix of plant protein, complex carbohydrates, and, most notably, a substantial amount of dietary fiber. Understanding the difference in macros between raw and cooked beans is key to accurate calorie counting. By incorporating this small but mighty ingredient into your diet, you can easily boost your intake of essential nutrients and support your overall health goals.

For more information on high-fiber foods, you can visit the Mayo Clinic's guide.

Frequently Asked Questions

No, a standard serving size for black beans is typically a ½ cup, which is roughly 86 grams and provides higher nutritional values. 40g is a smaller portion, suitable for adding to dishes like salads or soups.

Yes, black beans are a high-carbohydrate food. A 40g cooked serving contains approximately 9.5g of carbohydrates, primarily in the form of complex carbs, which provide sustained energy.

No, canned black beans can have different nutritional values, especially regarding sodium content. They also typically contain fewer calories per gram than dried beans cooked at home because of added water. Always check the specific product label.

Net carbs are calculated by subtracting dietary fiber from total carbohydrates. For a 40g cooked serving, with about 9.5g of total carbs and 3.5g of fiber, the net carbs are approximately 6g.

Yes, the high fiber and protein content in black beans can increase feelings of fullness and satiety. This can help reduce overall calorie intake and assist with weight management efforts.

Black beans are not considered a complete protein on their own, as they are low in the amino acid methionine. However, when paired with a grain like rice, they form a complete protein source.

To reduce gas, try soaking dried beans overnight and rinsing them thoroughly before cooking. Rinsing canned beans can also help. Gradually increasing your fiber intake and drinking plenty of water can also minimize discomfort.