• A Skeptical Introduction to Bodybuilding Supplements

    By Jay Diamond

    JD Portrait 2Six months after I started working out, I could see progress: I wasn’t on the verge of death during every workout. I was starting to do weight training, seeing and feeling the results. That’s when I considered augmenting my workouts with dietary supplements.

    It’s important to note that supplements aren’t meals – good overall nutrition is the first step to health, and most people can get most required nutrients from a well-rounded diet. I’m an omnivore, but I have friends who are pescatarians, vegetarians, and vegans. I’m not advocating one over another as long as it’s well-rounded, diverse, and hits the basic food groups.

    My criteria around supplements were simple:

    1. Do no harm. Or at least don’t do any more harm than the normal damage inflicted by living. Everything has an effect, everything has a side effect, but most are benign. I’m interested in bodybuilding for the long-term, so short-term gain at the expense of long-term pain was of no interest (i.e. Doubling the size of BOTH your biceps AND gonads would not be good). You may have different criteria.
    2. Must have a clinically proven positive effect that is germane to bodybuilding. I allow a lot of latitude here – so small, early studies are acceptable, but big long-term studies are optimal. Many supplements claim broad “feel good” results like lowering toxicity or generically boosting well-being– these aren’t germane to bodybuilding… or anything else that can be measured by science. “Clinically proven” also demands that there are recommended dosages required to obtain the positive effect.
    3. I must be able to experience the positive effect. Given the wide latitude in (2), a limited budget, and a lot of potential supplements to try, there’s no point ingesting something that doesn’t yield perceivable returns. Note that this is COMPLETELY subjective and anecdotal– and I accept this criteria knowing how easily fallible humans can be duped.

    Hyperbole in body building ads is prevalent, and weeding through the marketing hoopla to find the actual evidence can be daunting. Manufacturers often mix many supplements together for a magic proprietary “cocktail” that can be effectively marketed but mask efficacy of individual ingredients. To discover what’s actually meeting my criteria, I try to keep the ingredients pure (one at a time) and uncomplicated (not a lot of other ingredients). Figure out what works individually, then combine as desired.

    The first supplement that I started taking was protein. Let’s examine protein supplements under my criteria:


    • Kidney disease: This is the biggest negative concern cited regarding protein – one that I hear often. The issue is that increasing protein in one’s diet increases the work required by the kidneys to remove waste products. This is true… but it’s also associated with all foods to some extent, and unless massive amounts are ingested has never been shown to impact kidney function.  My doctor put this in perspective when we discussed protein supplements, referring to it as a “dietary choice”.
    • Heart Disease: Related closely to the type of protein ingested (I.e. lots of red meat or high fat dairy products). By avoiding high-fat sources of protein and with regular exercise, these risk factors are minimized. For example, eating fried vegetables or raw vegetables will yield a different nutrition profile- so intelligent choices for intake are required.
    • Allergies: These again greatly depend on the type of protein ingested and an individual’s sensitivity – but again, this is true with any ingested product (i.e. food).


    • Increased lean muscle mass: There’s little question that protein, which is made up of amino acids, is a foundational building block of muscle. The makeup of those amino acids in a given protein can affect muscle production – but that a discussion for a later blog. The bigger question is dosage (see below).

    Experience (anecdotal):

    • Increased muscle mass. I could see it, feel it, measure it. Protein doesn’t build muscle for you, but if gives you the fuel to build it with exercise. The results for me were unambiguous after a few months of training with this supplement.
    • Broader change in diet. To my surprise, protein supplements caused me to push a lot of other things out of my diet – unhealthy snacks, poor meal choices. Undoubtedly in conjunction with exercise, my craving started to change away from salty junk food & snacks to fruits, vegetables, and lean meat.  Protein supplements simply pushed a lot of carbohydrates out of my diet without effort or desire.


    The rule of thumb that bodybuilders have used for decades has been that for optimal muscle production, 1 gram (g) of protein for 1 pound (lb.) of body weight per day, EVERY day. But where does this actually come from and is it accurate? First, it’s odd that this “rule” states that protein intake is metric while body weight is imperial units… apparently 1g protein for 2.2 kg of body weight isn’t quite as memorable.

    So for a 175 lb. man, the traditional rule says that 175g of protein per day, every day are required. The science says only about 140g are required (75-80% of a gram per lb. of body weight). More adds no value and potentially creates health issues.

    A question that I’m often asked is why supplementation is necessary:

    Why not get all of your protein from food?

    Can I just have a chicken breast for dinner or eggs for breakfast and be DONE with it?

    Let’s do some quick calculations:

    Serving Size (g)
    Protein per serving (g)
    Chicken Breast (large)
    Egg (large)


    Using sample subjects:

    Weight (lbs.)
    Protein Req’d (g)
    Chicken Breasts


    For that 175 lb. man, that would mean 3 ½ large chicken breasts per day required to get his daily protein allotment… which is a HELL of a lot of food that comes with 30g of fat and >200 mg of both cholesterol and sodium.  Most men are also uninterested in eating 2 dozen eggs – or the >4g of cholesterol that comes with it.

    Obviously there are more diverse ways to ingest protein in your diet than only chicken or only eggs, but protein supplements (whey, soy, or casein powders, for example) solve the problem of not eating all the time in large quantities. I’ll discuss protein supplement types, timing in a future blog…


    Protein has demonstrable efficacy in building muscle with few side effects. It’s about as safe as a supplement can be. In later entries, I’ll discuss different types of protein and timing of ingestion.

    If you’re already working out but don’t take protein supplementation you’re simply not capitalizing on all of your work, and that begs the question – why not?


    1. Nutrition and healthy eating, Mayo Clinic
    2. New evidence on the effects of exercise on protein utilization during post-exercise recovery, Department of Health Sciences, Boston University.

    JD Portrait 1

    Jay Diamond is the founder of Reason4Reason – a skeptical activist group based in the San Francisco bay area. He holds dual masters degrees in engineering and business and has managed both startup companies and hundred-million-dollar programs for Fortune 50 companies. Growing up in Canada, he performed magic, studied science, and became aware of the skeptical movement. Jay has lectured around the world on science & technology, business, and skepticism. 

    Category: FeaturedFitnessJay DiamondNutrition & SupplementsSkepticism


  • Article by: Jay Diamond