Leucine inhibits myostatin-which foods are rich in leucine?

In a previous article I wrote about the effect of epicatechin on reducing myostatin, which may increase muscle mass (https://michaellustgarten.wordpress.com/2015/02/02/inhibit-myostatin-with-chocolate-increase-muscle-mass/). Are there any other ways to inhibit myostatin with the goal of increasing muscle mass?

10 grams of essential amino acids have been shown to reduce myostatin levels in skeletal muscle (Drummond et al. 2009). Because essential amino acids are found in high amounts in animal protein-containing foods, the answer to decrease myostatin would be to eat more protein, right?

Not so fast, because high protein diets (~20% of total calories), especially from animal sources are associated with an increased all-cause mortality risk in people younger than 65 years when compared with those eating a low protein diet (~10% of total calories; Levine et al. 2014). Fortunately, it isn’t just a bolus of essential amino acids that inhibits myostatin. Addition of the essential amino acid leucine to muscle cells inhibits myostatin expression, causing them to grow (Chen et al. 2013). If your goal is to maximize muscle mass but also, optimal health, what daily intake of leucine should you aim for while keeping your total protein intake low?

It has been reported that a leucine intake of 45 mg/kg/day (or more) may be required by athletes to maximize muscle protein synthesis (Mero 1999). For a 70 kg person, this translates into 3.15g of leucine per day (45 mg*70kg=3150mg, = 3.15g). Shown below is my 7-day average (5/21/2015-5/28/2015) protein intake. From the chart, my average daily leucine intake is 3.2 g. However, the nutrient tracking software that I use for some reason includes the total protein amount from my daily can of sardines but not its constituent amino acids. I used ndb.nal.usda.gov to get that info: 1 can of sardines has 1.6 g of leucine. In total, my daily leucine intake is 4.8 g/day. My body weight is currently at 69.1 kgs. These values put me at 70 mg leucine/kg body weight/day (70 * 69.1kg = 4837 mg, = 4.8 g), which is well above the 45 mg/kg/day value above.

leu

So which foods are rich in leucine? Below I’ve ranked foods based on their leucine content (in grams) divided by total calories. Egg whites and cod fish are the all-stars for leucine content per calorie. Chicken and beef are relatively good sources of leucine. Although spinach is better than skim milk when comparing its leucine/calorie content, none of the vegetables or beans come close to the leucine/calorie content found in egg whites or cod fish.

leucine calorie

If you’re interested, please have a look at my book!

References:

Chen X, Huang Z, Chen D, Yang T, Liu G.MicroRNA-27a is induced by leucine and contributes to leucine-induced proliferation promotion in C2C12 cells. Int J Mol Sci. 2013 Jul 8;14(7):14076-84.

Drummond MJ, Glynn EL, Fry CS, Dhanani S, Volpi E, Rasmussen BB. Essential amino acids increase microRNA-499, -208b, and -23a and downregulate myostatin and myocyte enhancer factor 2C mRNA expression in human skeletal muscle. J Nutr. 2009 Dec;139(12):2279-84.

Levine ME, Suarez JA, Brandhorst S, Balasubramanian P, Cheng CW, Madia F, Fontana L, Mirisola MG, Guevara-Aguirre J, Wan J, Passarino G, Kennedy BK, Wei M, Cohen P, Crimmins EM, Longo VD. Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population. Cell Metab. 2014 Mar 4;19(3):407-17.

Mero A. Leucine supplementation and intensive training. Sports Med. 1999 Jun;27(6):347-58

Homemade peanut butter and berry jelly!

Here’s my recipe for homemade peanut butter and jelly!

Homemade PB&J

Whole wheat bread: 600g whole wheat flour, 1.5g yeast, 80g brown sugar, 350 mL water. Put all ingredients into the bread machine for 90 minutes.

56 g shelled raw peanuts, ground in the food processor. Add 1 teaspoon of peanut oil after the peanuts are ground.

1 large cup of mixed berries, cooked until the water is boiled off (~20 minutes).

Why eat it from the store, as you’re probably also eating the chemicals and preservatives that are added to increase shelf life? Enjoy!

If you’re interested, please have a look at my book!

Inhibit myostatin with chocolate, increase muscle mass?

Mice that don’t have myostatin have dramatically increased muscle mass:

MyostatinMs

Myostatin levels increase during aging, a finding that may (at least partially) explain age-related decreases in muscle mass (Basaria and Bhasin 2012). Is there anything that we can do besides strength-training (Snijders et. al 2014) to decrease myostatin levels?

To address this question, Gutierrez-Salmean and colleagues (2014) supplemented young and old mice and humans (29 vs. 62y) with epicatechin, which is found in may foods (see the Table below). They found that in both mice and humans, myostatin increased during aging. However, epicatechin supplementation decreased muscle myostatin levels in both young and old mice and humans! Although they did not report how muscle mass changed as a result of epicatechin supplementation, grip strength significantly improved after only 7 days of supplementation in the older adults. Although this study had a relatively small sample size (20 total subjects), that a food component can reduce myostatin levels is an interesting finding.

So, which foods are rich in epicatechin?

Atop the list are cocoa containing products. It is important to note that 50mg/day of epicatechin were provided to the human volunteers of the Gutierrez-Salmean study. Obtaining 50mg of epicatechin may be relatively easy, if one chooses wisely from the foods listed in the Table. For example, drinking 20 ounces of white, black or green tea would yield 10-46mg of epicatechin. Homemade chocolate (https://michaellustgarten.wordpress.com/2014/09/21/homemade-chocolate-in-2-minutes/) containing 1 ounce of cacao beans yields ~27 mg of epicatechin.

epicatechin foods table

If you’re interested, please have a look at my book!

References:

Epicatechin data: http://www.ars.usda.gov/SP2UserFiles/Place/80400525/Data/Flav/Flav_R03.pdf

Basaria S, Bhasin S. Targeting the skeletal muscle-metabolism axis in prostate-cancer therapy. N Engl J Med. 2012; 367:965–967.

Gutierrez-Salmean G, Ciaraldi TP, Nogueira L, Barboza J, Taub PR, Hogan MC, Henry RR, Meaney E, Villarreal F, Ceballos G, Ramirez-Sanchez I. Effects of (-)-epicatechin on molecular modulators of skeletal muscle growth and differentiation. J Nutr Biochem. 2014 Jan;25(1):91-4.

Snijders T, Verdijk LB, Smeets JS, McKay BR, Senden JM, Hartgens F, Parise G, Greenhaff P, van Loon LJ. The skeletal muscle satellite cell response to a single bout of resistance-type exercise is delayed with aging in men. Age (Dordr). 2014;36(4):9699.