Aaron Deere is a sports nutritionist, functional medicine consultant and advanced personal trainer. He is based in London.
It’s hard to always turn down invitations for after-work drinks or a weekend drink with your mates. But if you want to build the best body possible then you know that sleep is your friend and that booze is the enemy. But what is the real impact of alcohol on your body composition goals?
We all know that chronic alcohol abuse can lead to many serious health conditions, including liver disease, cirrhosis, gastritis, pancreatitis and osteoporosis. You may also be aware that moderate alcohol consumption has been shown to be beneficial to health in the general population. One to two units of alcohol per day – that’s equivalent to a small glass of wine or a bottle of lager – can improve insulin sensitivity, cardiac function, and blood lipid ratios[1,2].
But the general population are not trying to maximise muscle mass and minimise body-fat levels, so how does alcohol affect those with these aims?
The calorie cocktail
A gram of ethanol, the predominant form of alcohol found in beer, wines and spirits, contains approximately 6.9 calories. That’s more than the four calories in a gram of protein and a gram a carbs, but less than the nine calories in a gram of fat.
Despite the high calorie intake per gram, a lot of epidemiological evidence suggests alcohol intake alone is not associated with weight gain. Research – and indeed common sense – suggests that it is the calories from alcohol in addition to the extra food that is consumed that results in weight gain.
This makes sense because alcohol does not affect satiety in the way carbs, fats and protein do. In fact the opposite occurs as the lowering of blood-sugar levels caused by alcohol stimulates hunger, which often leads to poor food choices because the disinhibition of impulse control follows excessive alcohol consumption.
Alcohol and testosterone
The anecdotal belief is that alcohol lowers testosterone levels within the body, which is detrimental to the body-composition effects of resistance training, and research backs this up.
However, the effect is not as pronounced as many may believe. A three-week study in which men and women consumed 30g to 40g alcohol per day – that’s around three pints of beer – showed only a 6.8% reduction in testosterone in men, and no change in women.
For alcohol to significantly lower testosterone much larger amounts of alcohol needed to be consumed. One study proved that 120g of alcohol – or around 10 pints of beer – lowered testosterone levels in men by 23% for up to 16 hours post consumption.
The effects of alcohol consumption post-exercise have shown varying dose-dependent effects on recovery. Animal and in vitro studies showed impairment of protein synthesis in cases of chronic and acute alcohol consumption[6,7].
Similar results were shown in humans, with acute consumption (12 units) immediately post workout resulting in reduced rates of myofibrillar protein synthesis, which impairs recovery and adaptation to training. Moderate alcohol consumption was again shown to have a minimal effect. The research suggests that moderation is key when wanting to consume alcohol and improve body composition.
The consumption of moderate amounts of alcohol will have limited negative effects on the body and can in fact provide health benefits. It is only when acute amounts of alcohol are consumed that the impairment of training adaptations become more pronounced.
1 Arima, H., Kiyohara, Y., Kato, I., Tanizaki, Y., Kubo, M., Iwamoto, H.,… & Fujishima, M. (2002). Alcohol reduces insulin–hypertension relationship in a general population The Hisayama study. Journal of clinical epidemiology, 55(9), 863-869.
2 Das, S., Santani, D. D., & Dhalla, N. S. (2007). Experimental evidence for the cardioprotective effects of red wine. Experimental & Clinical Cardiology, 12(1), 5.
3 Yeomans, Martin R. “Alcohol, appetite and energy balance: is alcohol intake a risk factor for obesity?.” Physiology & behavior 100.1 (2010): 82-89.
4 Sierksma, A., Sarkola, T., Eriksson, C. J., Gaag, M. S., Grobbee, D. E., & Hendriks, H. F. (2004). Effect of Moderate Alcohol Consumption on Plasma Dehydroepiandrosterone Sulfate, Testosterone, and Estradiol Levels in Middle‐Aged Men and Postmenopausal Women: A Diet‐Controlled Intervention Study. Alcoholism: Clinical and Experimental Research, 28(5), 780-785.
5 Välimäki, M., Tuominen, J. A., Huhtaniemi, I., & Ylikahri, R. (1990). The pulsatile secretion of gonadotropins and growth hormone, and the biological activity of luteinizing hormone in men acutely intoxicated with ethanol. Alcoholism: Clinical and Experimental Research, 14(6), 928-931.
6 Preedy, V. R., Keating, J. W., & Peters, T. J. (1992). The acute effects of ethanol and acetaldehyde on rates of protein synthesis in type I and type II fibre-rich skeletal muscles of the rat. Alcohol and Alcoholism, 27(3), 241-251.
7 Hong-Brown, L. Q., Frost, R. A., & Lang, C. H. (2001). Alcohol impairs protein synthesis and degradation in cultured skeletal muscle cells. Alcoholism: Clinical and Experimental Research, 25(9), 1373-1382.
8 Parr, E. B., Camera, D. M., Areta, J. L., Burke, L. M., Phillips, S. M., Hawley, J. A., & Coffey, V. G. (2014). Alcohol ingestion impairs maximal post-exercise rates of myofibrillar protein synthesis following a single bout of concurrent training. PloS one, 9(2), e88384.