Are you looking to add more muscle? Of course you are!

Could something that you are likely taking on daily basis be slowing your progress?

A recent study (Makanae Y et al. 2012) showed that vitamin C may results in less muscle growth!

Oh crap! I can already hear vitamin C bottles hitting the trash.

A new study looked at this question.  They investigated the effects of vitamin C and muscle size indirectly via muscle damage. While muscle damage is not an absolute requirement to increase muscle size and strength, it does help.

Should you toss all your vitamin C supplements along with your new citrus-free diet?

 Not so fast, my amigo.

There are 3 massive things to keep in mind when reading this new study.

1) Rats

This is a rat study, and last I checked your whiskers are not that long. Rat studies, while useful, do not always directly transfer to humans.

2) Dose

The dose used was 500 mg / kg; so if we convert directly to humans (a big “if” since you are not a rat, I hope), and you weigh 100 kgs (220 lbs), that is 50 grams of vitamin C.

For simple math, let’s assume that the  vitamin C pills you are taking are 500 mg, so that would be 100 pills at once.

Yep, one heck of a large dose and is not recommended. That is enough to keep you doing the Wilford Brimley two-step in the bathroom for quite some time as it will rage a complete war on your guts.

3) Massive Overload Stimulus 24/7

The model of muscle hypertrophy used was “synergist muscle ablation.” I know that sounds all fancy, but basically scientists surgically removed the gastrocnemius and soleus muscles of the right hindlimb to overload the remaining plantaris muscle.

Basic Anatomy To Get Bigger Muscles

Your lower leg has 3 main muscles that work to help you stand up on the balls of your feet; the 1) soleus, 2) plantaris, and 3) calf (aka the gastrocnemius).


The soleus and plantaris muscle are deep and sit under the calf muscle (which you can easily feel if you grab your lower leg). All three of these muscles work together to help you point your toes (“plantarflexion” for the anatomy geeks out there).

Now imagine if I cut your calf and soleus muscles and only left the plantaris muscle to do all of the work. You would now have a major overload stimulus to the muscle every time you took a step.

Picture this, you start a new job as a waiter at a fancy gourmet restaurant. The kind where you can pick from 4 kinds of bottled water and everything is a la carte. Business is good and you only have 3 tables a night at any one time. Life is good.

Now imagine your boss does not take his meds, and in a fit of rage, fires 2 other servers. You need to pick up the slack before you lose your job and the customers throw expensive French bottled water on you. Instead of 3 tables you now have 9 tables and are running around like a spazzed-out squirrel on meth in an attempt to keep your job.

Major overload!

 Same idea here with our fury rat friends as there is only 1 muscle left to take the work of what is normally handled by 3 – major overload.

Overload and Muscle Size

Everyone agrees that overload is key for increasing muscle size and strength. While this procedure does provide huge amounts overload, it is not recommended and is very painful according to what the rats told me.   Insert mental image of the rats limping around with huge lower legs here _______.

Early rat studies from the 1970’s using the same overload model showed that they could not crush the hypertrophy response no matter what they did to the poor little guys–no thyroid, low protein, de-nutting (aka castration – youch), etc,  it did not matter.  Even after all those horrible things, the darn rat muscle in the lower leg still got bigger.

While it did blunt the increase in muscle size, it did not send it to zero as they first suspected. This is further evidence that the local overload to the muscle is extremely important. Score another one for lifting weights!

Vitamin C and Muscle Size

Back to the rat study. While it is true that oral vitamin C did decrease the overload-induced skeletal muscle hypertrophy (size), the reduction was not huge in addition to the 3 limitations I discussed above.

In Summary: How to Enjoy Bigger Muscles with Vitamin C

I would not toss my Vit C out yet, but consuming tons of it is probably not the best idea if you are trying to get bigger in the gym or stay healthy. Some is good, more is not always better desipte what the hyooooooge sides of beef dudes in the gym tell you.

This study is the first step to look at the potential reduction in muscle size using large amounts of vitamin C and future studies will shed more light on this mechanism.  Until then, I would not be worried about some vitamin C reducing your effects of hard work in gym picking stuff up and setting it down again.

Beware of others touting that vitamin C is bad for your muscles….unless you are indeed a rat taking several grams per day with 2 cut tendons in your lower leg.  Then you can worry.

Mike T Nelson

Makanae Y, Kawada S, Sasaki K, Nakazato K, Ishii N. “Vitamin C administration attenuates overload-induced skeletal muscle hypertrophy in rats.” Acta Physiol (Oxf). 2012 Nov 26. doi: 10.1111/apha.12042. [Epub ahead of print]