Leucine Rich Foods for Optimal Muscle Protein Synthesis

Research by Professor Don Layman has highlighted the importance of foods with plenty of leucine for muscle growth, with older adults requiring at least 2.5 g of the amino acid leucine per meal to stimulate muscle protein synthesis. 

If you’ve ever wondered what foods high in leucine look like, you’re in luck. This article will show you the quantity of popular leucine-rich food foods required to get the minimum amount of leucine required to activate muscle protein synthesis.

Which Foods are Highest in Leucine? 

The infographic below shows the amount (in grams) of various popular foods required to get 2.5 grams of leucine and the calories they provide. 

The table below shows these popular foods ranked based on the calories required to get 2.5 g of leucine.  Remember, this is the minimum amount needed to activate muscle protein synthesis.  You may need to eat more depending on your goals, current muscle mass, and activity level.

food	calories	grams	servings
egg whites	129	249	1 cup
turkey breast	141	96	3.4 oz
cod	141	135	0.8 fillet
chicken breast (skinless)	150	134	0.65 large
sirloin steak	152	142	3.4 oz
Greek yogurt (non-fat)	153	260	1 cup
shrimp/prawns	161	162	27 large
pork loin (lean)	161	113	4 oz
ribeye filet (fat trimmed)	163	88	3.1 oz
liver	181	89	3.4 oz
cottage cheese (low-fat)	194	239	1 cup
ground beef (95% lean)	205	142	4.2 oz

Regardless of your preferred way of eating, you need adequate leucine to activate muscle protein synthesis.  The infographics below show popular leucine-rich foods from different food groups required to get a minimum of 2.5 g of leucine.

Leucine-Rich Meat

Animal-based foods, like turkey breast, chicken breast, beef and pork, are rich in leucine.  Hence, they will provide the leucine you need with fewer calories. 

food	calories	grams	servings
turkey breast	141	249	1 cup
chicken breast (skinless)	150	134	0.65 large
roast beef	150	143	3.3 oz
sirloin steak	152	142	3.4 oz
pork loin (lean)	161	113	4 oz
ribeye filet (fat trimmed)	163	88	3.1 oz
liver	181	89	3.4 oz
ground beef (95% lean)	205	134	4.2 oz
flank steak (fat eaten)	209	166	3.6 oz
filet mignon	216	106	3.7 oz
chicken thigh (skinless)	229	119	1.5 large
chicken drumstick (skinless)	236	142	4.8 oz

Leucine-Rich Dairy & Egg

Lower-fat dairy products and eggs are also a great way to get bioavailable leucine. 

However, as shown below, you’ll need to consume a lot more calories to get the minimum amount of leucine from full-fat dairy.  For example, three large eggs will only give you 1.6 g of leucine.  You’d need five whole eggs to get 2.5 g of leucine. 

food	calories	grams	servings
egg whites	129	249	1 cup
Greek yogurt (non-fat)	153	142	3.4 oz
protein powder (whey)	177	47	1.5 scoops
cottage cheese (low-fat)	194	239	1 cup
parmesan cheese	284	72	0.5 cup
milk (low-fat)	330	784	3.1 cups
Jarlsberg cheese	332	84	4 slices
Gruyere cheese	333	80	2.8 oz
Swiss cheese	336	86	4 slices
gouda cheese	347	98	4.6 slices
Edam cheese	352	98	3.5 oz
whole egg	366	236	5.5 medium

Leucine-Rich Seafood

Seafood is also an excellent source of bioavailable leucine. 

Seafood tends to be lean and protein-packed, providing plenty of leucine with minimal calories.

food	calories	grams	servings
cod	141	135	0.8 fillet
snapper	153	286	0.7 fillet
tilapia	157	123	4.3 oz
shrimp/prawns	161	162	27 large
tuna	190	132	4.7 oz
octopus	195	119	4.2 oz
mackerel	207	133	4.7 oz
squid	211	201	7.1 oz
salmon (canned)	225	143	1.8 cans
scallops	232	209	7.4 oz
mussels	260	151	15 large
oysters	313	387	7 large

Leucine-Rich Beans, Legumes, Nuts & Seeds

Plant-based foods also contain the amino acid leucine; however, people on a plant-based or vegetarian diet need to consume more energy to get the leucine required to activate muscle protein synthesis. 

For example, you will need to consume nearly five times as much energy to get the same amount of leucine from corn vs egg whites.  So, it’s important to choose your leucine sources on a plant-based diet wisely. 

food	calories	grams	servings
lupini	252	212	1.3 cups
natto	350	166	1 cup
edamame	400	330	2.2 cups
tempeh	401	209	7.4 oz
kidney beans	431	340	1.5 cups
lentils	445	384	2 cups
oat bran	448	182	2 cups
black beans	466	353	2.1 cups
pinto beans	467	327	2 cups
tofu	516	498	18 oz
baked beans	580	617	2.4 cups
corn	585	878	5.3 cups

Benefits of Leucine-Rich Foods

One of the reasons many people refer to 30 g of protein as the minimum amount per meal is that that’s the amount typically required to get 2.5 g of leucine from most foods.  Professor Don Layman’s research emphasises leucine for muscle growth, showing older adults require at least 2.5 g of leucine to activate muscle protein synthesis, which is vital for muscle building and repair. 

With less than this, the protein you eat is used only to maintain your vital organs, which are a higher priority than your muscles.  While leucine is required to activate muscle protein synthesis, you need all the essential amino acids to build and repair your body, so it’s not as simple as supplementing with leucine. 

How Many Meals Per Day to Get Enough Leucine? 

Most people struggle to get all the protein and leucine they need in a single meal.  Professor Layman also wisely recommends that you ‘bookend’ your day with a solid dose of protein at your first and last meal to ensure your body has adequate amino acids in your bloodstream throughout the day.  

If you’re trying to lose weight, two meals a day with a snack in between to tide you over tends to be a great approach.  If you’re more active, you’ll need to eat more often to get the required energy and protein. 

How Much Leucine Do You Need?

The current Recommended Daily Allowance for leucine for adults is 42 mg/kg body weight per day, which equates to 2.9 g of leucine per day for a 70 kg person.  However, Professor Don Layman and others argue that this amount is woefully low to prevent sarcopenia. 

The chart below shows that older adults require around 2.5 g of leucine or 30 g of protein per meal to activate muscle protein synthesis.  Above 3.0 g of leucine per peal, the benefit of additional protein for muscle protein synthesis tapers off.  So, while 2.5 g of leucine per meal is the minimum required to activate muscle protein synthesis, you need at least 3.0 g per meal to maximise muscle protein synthesis. 

The chart below shows the satiety response to leucine in our food based on 313,836 data from free-living people, indicating that we eat the most when we consume around 4.7 g of leucine per 2000 calories. 

This suggests that our bodies crave a minimum amount of leucine and will eat more to get the minimum amount we require.  However, we eat less if we pack in more leucine to our energy budget.   

Interestingly, the minimum of 4.7 g of leucine per 2000 calories highlighted by our data analysis is similar to Professor Layman’s minimum of 2.5 g of leucine with two meals. 

Target Leucine Intake for Fat Loss

As shown in the chart above, people who get our Optimal Nutrient Intake of 14 g of leucine per 2000 calories consume 24% less energy than those who get 4.7 g of leucine per 2000 calories (i.e. the leucine bliss point). 

You can think of the bliss point as the perfect amount of leucine for fat gain (i.e. the leucine bliss point), while 14 g/2000 calories is a stretch target for increased satiety and fat loss (i.e. the Optimal Nutrient Intake). 

The table below shows the amount of leucine (in grams) corresponding to the fat gain vs fat loss settings for various calorie intakes. 

calories	fat gain	fat loss
1000	2.4	7.0
1250	2.9	8.8
1500	3.5	10.5
1750	4.1	12.3
2000	4.7	14.0
2250	5.3	15.8
2500	5.9	17.5

If you want to lose fat and gain muscle, you can work to increase your intake of leucine-rich foods using the fat loss targets as a stretch goal. 

Do You Need to Worry About Your Leucine Intake? 

If you’re following an omnivorous diet and getting plenty of protein, you don’t need to stress about micromanaging your leucine intake.  Our analysis shows that we have the strongest satiety response to the protein in our food, with a bliss point at 12.5% and an Optimal Nutrient Intake of 40% protein.   If you’re getting plenty of protein from an omnivorous diet, you’ll also get plenty of all the amino acids, including leucine.   

However, plant-based foods tend to contain less leucine, so if you’re following a vegan or vegetarian diet, monitoring and managing your leucine intake will be useful to ensure you have enough to prevent sarcopenia. 

How to Determine if You Are Getting Enough Leucine

The simplest way to determine if you’re getting enough leucine is to track your typical diet in Cronometer for a few days to see how your protein intake aligns with the fat loss vs fat gain targets above. 

In our Macros Masterclass, we guide our Optimisers to gradually increase their protein % prioritising protein and dialling back energy from fat and/or carbohydrates.  In addition to protein, our satiety algorithm also guides Optimisers to prioritise the other nutrients, like calcium, potassium and iron, that align with greater satiety and eating less. 

If you’re looking for nutritious, higher-protein recipes, you can download free samples of our maximum nutrient density, fat loss or high protein:energy NutriBooster recipes here. 

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• Leucine-Rich Foods for Optimal Muscle Protein Synthesis
• Cracking the Hunger Code: Our Data-Driven Satiety Algorithm!
• Comprehensive Guide to Amino Acids: Types, Functions, and Food Sources
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