What Type of Fat is Good for Bulking? Your Comprehensive Guide

December 1, 2025 •

3 min read

Research has shown that consuming polyunsaturated fats during a bulking phase can lead to more muscle mass gain and less body fat accumulation compared to saturated fats. This distinction is critical for anyone wondering what type of fat is good for bulking to achieve a lean, effective bulk.

Quick Summary

This guide explains the different types of dietary fats and their specific roles in a bulking diet, focusing on the benefits of monounsaturated and polyunsaturated fats, especially omega-3s, for muscle growth and hormone function.

Key Points

Prioritize Unsaturated Fats: Focus on monounsaturated and polyunsaturated fats from sources like nuts, seeds, and avocados to support hormone function and minimize fat gain. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}
Embrace Omega-3s: Found in fatty fish, walnuts, and flaxseeds, omega-3s are crucial for reducing post-workout inflammation and supporting muscle protein synthesis. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}
Consume Enough Calories: Fats are calorie-dense, helping you achieve the surplus needed for muscle gain. Aim for 20-30% of daily calories from healthy fats.
Support Hormone Production: Adequate healthy fat intake is essential for producing anabolic hormones like testosterone and growth hormone, which drive muscle building. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}
Choose Calorie-Dense Snacks: Nuts, seeds, and nut butters offer high calories and healthy fats, making them ideal for convenient bulking snacks. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}
Moderate Saturated Fats: While not all saturated fat is detrimental, research suggests overconsuming it leads to more body fat accumulation than unsaturated fats. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}
Avoid Trans Fats: Industrially produced trans fats offer no health benefits and should be completely avoided during a bulking phase. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}

A successful bulking phase requires a strategic approach to nutrition, and dietary fats are a cornerstone of this plan. Often seen simply as a source of dense calories, fats play a far more intricate role in muscle growth, hormone regulation, and overall health. Not all fats are created equal, however, and prioritizing the right types is key to achieving muscle gain without excessive body fat accumulation.

The Importance of Fats for Bulking

Beyond merely providing calories, fats are essential for a variety of physiological functions critical to bodybuilding. Fats are the most energy-dense macronutrient, important for creating a calorie surplus. They are also crucial for producing anabolic hormones like testosterone, vital for muscle development. Adequate fat intake is necessary for absorbing fat-soluble vitamins (A, D, E, K), which support muscle and bone health. Additionally, omega-3 fatty acids, a type of polyunsaturated fat, help reduce inflammation caused by intense training, aiding recovery.

The Best Fats for Muscle Growth

Focusing on unsaturated fats, particularly monounsaturated and polyunsaturated fats, is the ideal strategy for a lean bulk. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}

Monounsaturated Fats

These fats are beneficial for heart health.

Sources: Avocados, olive oil, and nuts like almonds, cashews, and peanuts are excellent sources.

Polyunsaturated Fats

These are 'essential' fats the body needs from food.

Omega-3 Fatty Acids: Important for muscle protein synthesis and reducing inflammation. Sources include fatty fish (salmon, mackerel), flaxseeds, chia seeds, and walnuts.
Omega-6 Fatty Acids: Also essential, but should be balanced with omega-3s. Sources include sunflower, soybean, and corn oils. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}

Saturated vs. Unsaturated Fats for Bulking

Choosing the right type of fat influences body composition during a calorie surplus. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}


Feature	Unsaturated Fats	Saturated Fats
Bulking Effect	Promotes more muscle mass and less fat gain	Increases total fat mass, particularly visceral fat
Metabolic Health	Improves insulin sensitivity and metabolic markers	High intake linked to increased visceral fat and metabolic issues
Hormone Support	Supports optimal testosterone production and overall hormone function	Essential for hormone synthesis, but excessive intake is not beneficial
Best Sources	Avocados, nuts, seeds, olive oil, fatty fish	Full-fat dairy, lean meats, coconut oil (in moderation)

How to Incorporate Healthy Fats into Your Bulking Diet

Strategic food choices can enhance healthy fat intake. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}

Add healthy fat sources: Include avocados in meals, drizzle olive oil on dishes.
Use nut butters: Add to shakes or spread on toast.
Snack on nuts and seeds: Convenient, calorie-dense snacks.
Eat fatty fish: Aim for 2-3 servings weekly for omega-3s.
Cook with healthy oils: Use olive, avocado, or canola oil. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}

Conclusion

For bulking, prioritizing unsaturated fats like monounsaturated and polyunsaturated fats (especially omega-3s) is key. These support hormone production, nutrient absorption, and muscle protein synthesis. While saturated fats are acceptable in moderation, favoring unsaturated fats helps gain more lean mass and less unwanted body fat. Making informed fat choices is vital for a successful bulk. {Link: Happiest Health https://www.happiesthealth.com/articles/fitness/how-fat-aids-in-building-muscle-mass}

ISSA's guide to choosing good fats for muscle building

Frequently Asked Questions

Fats are crucial for bulking because they are a dense source of energy, providing 9 calories per gram to help achieve the calorie surplus needed for muscle growth. They also play a vital role in hormone production, aid vitamin absorption, and help regulate inflammation.

Monounsaturated fats (found in olive oil, avocados, nuts) have one double bond in their carbon chain and are known for heart health. Polyunsaturated fats (like omega-3s and omega-6s) have multiple double bonds and are 'essential,' meaning the body cannot produce them. Omega-3s, especially, are known for their anti-inflammatory properties.

Yes, but in moderation. While saturated fat is needed for hormone synthesis, studies indicate that excessive saturated fat intake during a calorie surplus leads to greater body fat gain compared to unsaturated fats. Keep intake limited and prioritize unsaturated sources.

For most individuals, a daily fat intake of around 20-30% of total calories is recommended during bulking. This translates to a specific gram target depending on your total calorie goals.

Excellent sources of healthy fats include avocados, olive oil, fatty fish (salmon, mackerel), nuts (almonds, walnuts), seeds (flaxseeds, chia seeds), and nut butters with no added sugar.

Omega-3s, especially EPA and DHA found in fatty fish and supplements, aid muscle growth by reducing inflammation after intense workouts, speeding up recovery, and enhancing muscle protein synthesis.

Yes, adequate fat intake is crucial for optimal hormone production, including testosterone. Studies show that a diet with too little fat can negatively impact testosterone levels, which is essential for muscle anabolism.