Spinach and Muscle Growth

Yum, spinach! It’s one of my favorites and a staple in my house. I like to use it as a base for smoothies, salads, and wraps. Occasionally, I do cook it, but only enough so that is turns an even brighter shade of green. My kitten is a fan too, insisting that I give her a leaf whenever I open the bag.

Spinach is thought to have originated in Persia and is in the same family as both beets and quinoa (which make for a fantastic veggie bowl, but that's a post for a different day). From Persia, the vegetable traveled to India and then to China, where it was known simply as “Persian Vegetable.” Spinach moved westward, gaining popularity in Europe as it was a vegetable that grew quickly in the early spring.  This Provided a welcome break in the monotony of winter stores. 

Most people associate spinach with Popeye. That famous Sailor Man inhaled his canned leafy greens making his muscles explode as he saved Olive Oyl time and time again. As a result, spinach sales during WWII increased by almost 33%. But is there truth here? Can vegetables cause muscle gains? 

To answer this, let’s first explore how the body builds muscle. 

Your muscles are made up of fibers that are grown in utero and defined shortly after you are born. From there, muscle size can only be increased by straining the muscle fibers through adding stress (i.e. lifting weights or working out). This stress causes the fibers to increase in diameter, or sometimes in length.

The importance of protein

Protein is digested and broken down into amino acids. Amino acids are then absorbed into the bloodstream and taken to the muscles, where they can start rebuilding and repairing. Your body needs 20 different amino acids to do this, but 11 can be synthesized in the body. The other 9 need to be found and ingested to create complete proteins. 

The Spinach Connection

Spinach has all 9 amino acids making it a complete protein food! I was so surprised and excited about this fact, I had to check a couple of sources, listed at the end.

Strong Muscles from Wimpy Spinach
(Side note, did you know that “wimpy” was word created because of J. Wellington Wimpy, a character in Popeye?)

Dr. Maria Parr, from Freie University in Berlin, conducted a study testing the effect of spinach extract on 46 athletes. The extract contained ecdysterone, a naturally occuring phytosteriod, thought to increase protein synthesis in muscles. 

The athletes received doses of different levels of ecdysterone and some received a placebo. At the end of the 10-week study, the athletes who received the ecdysterone were found to have higher levels of muscle mass. Because this was a naturally occurring chemical, there were no signs of toxicity in the liver or kidneys.

Dr. Parr’s study concluded that ecdysterone had an effect on athletic performance. However, it should be noted that the lowest amount of ecdysterones given to the athletes was the equivalent of 250 g - 4kg (.5 - 8 pounds, in American) of spinach per day!

A similar study was conducted back in 2008 by US Scientists. They fed ecdysterone to human cells and rats which caused a 20% increase in protein growth. The rats experienced a 24% increase in grip strength, more than the rats who were dosed with a steroid called methandrostenolone.

Oxalates: Spinach’s Dark Side
This is the buzzkill portion. Just one-half cup of spinach can contain up to 250 mg of oxalates, which are compounds that are normally excreted through the digestive system. Two-hundred and fifty mg is considered to be the upper echelon of the amount you should consume daily (For reference, to get 250 mg of oxalates in kale, you would need to consume 125 cups). Consuming too many oxalates can cause build up in the kidneys and create kidney stones. Long term effects can include kidney failure. So, that 8 pounds of spinach mentioned earlier? Probably not a great idea. 

To Eat or Not to Eat?

When I first heard about the spinach muscle study, I was so excited that the secret to building muscle could be found from Popeye. Maybe cartoons have had all of the answers all along. Do cats who eat lasagna have a more acute sense of how terrible Mondays are? Does eating pizza make one a ninja?

I wanted this article to be about natural options to steroids. But, the science says otherwise. I do still love spinach and will continue to eat it, a lot (I just had some for dinner!). There are still massive health benefits from eating spinach and I encourage you to find ways to get it in your diet if you aren't already. Dark, leafy greens are important to have at every meal, but mix it up with some kale or bok choy. If you are looking for ecdysterones, try spinach’s sister, quinoa. If you are really desperate, you can purchase ecdysterone extract online, but this isn't recommended. Dr. Parr requested this to be added to the list of banned substances. 

As with everything, moderation is key. Variety is also important to ensure that your body gets all of the nutrients it needs. Most importantly, don’t eat 8 pounds of anything.

Sources:
Muscle Growth & Exercise
Plant Power: The 10 veggies with the most protein
National Nutrient Database
Spinach Supplement May Increase Muscle Strength
“Ecdysteroids as non-conventional anabolic agents:Pharmacodynamics, pharmacokinetics, and detection of ecdysterone”
Spinach Really Does Help Build Muscles
Nutrition Facts: Oxalates in Spinach and Kidney Stones: Should we be concerned?
Nutrition Facts: Kidney Stones in Spinach, Chard, and Beet Greens: Don't Eat Too Much

Here is Minerva Enjoying a Leaf