Can drinking red wine really be good for you?
Can I still drink if I want to lose weight?
I train really hard during the week, don't I deserve to have a few drinks on the weekend?
Short answer: it depends. [on your health, lifestyle, and goals.]
*Side note: Alcohol is just another term used for ethanol (the by-product of carbohydrate fermentation) so when I refer to alcohol, I am talking about all forms (beer, wine, and liquor).
Some may argue that alcohol can be considered a fourth macronutrient (a dietary source of calories), but NOT because it is essential in the diet or provides nutrients, but rather because it supplies calories. Remember: the three major macronutrients that comprise the diet (and therefore provide calories in the diet) are protein, carbohydrate, and fat where all three are essential to life, provide nutrients, AND provide calories. They are termed macronutrients because they are present in food in relatively large amounts and we require them in relatively large amounts, compared to the smaller amounts of micronutrients (vitamins and minerals) needed. *Think about comparing grams of macronutrients to micrograms of micronutrients.
If we compare dietary sources of calories:
1g carbohydrates= 4 calories
1g protein= 4 calories
1g fat= 9 calories
1g alcohol= 7 calories
HOWEVER, the fact that alcohol contains calories is largely where the similarities end because it also lacks nutrients and is NOT essential for functioning (so calling it a macronutrient isn't entirely accurate). Further, not only does alcohol NOT contain nutrients nor perform an essential function in the body, but the accumulation of its by-products can be toxic and where chronic ingestion of alcohol can actually inhibit absorption of nutrients in the intestine like vitamin B1, folate, and zinc, among others. (Nix, 2013) [It can also be referred to as an anti-nutrient because it inhibits absorption of these nutrients.] What is most concerning is the fact that alcohol is considered a 'priority fuel' which means that it is metabolized first (regardless of anything else in the system) because the body sees it as a toxin that it must quickly metabolize and excrete (to eliminate it from the body).
When you drink alcohol, it is absorbed immediately in the stomach and small intestine (if the stomach is lined with food, then the absorption occurs at a slower rate) where it is sent directly to the liver to be metabolized. (Nix, 2013) Classified as a 'priority fuel' the liver sees it as a toxin and thus immediately works to metabolize alcohol (detoxify it) into a by-product that can be eliminated from the body post-haste, so as to avoid toxicity from accumulation. During this process of alcohol metabolism, it is oxidized to acetaldehyde (which can further form acetate and acetyl CoA) of which can enter the Kreb's cycle to be oxidized for energy (so yes, those calories can be used as energy). (Gropper and Smith, 2013)
HOWEVER, alcohol metabolism occurs with specific liver enzyme systems that function solely as detoxification pathways, which means that you are NOT oxidizing this energy via muscle or fat tissue, but using your liver's detoxification systems to burn through (oxidize) the alcohol. (Gropper and Smith, 2013) These detoxification liver enzymes are also responsible for detoxifying medications, caffeine, aspirin, etc which is why there is a increased threat of liver damage with co-ingestion and/or chronic high ingestion of all of these compounds.
Let's compress all of that into one final statement: Yes alcohol provides calories in the diet that can be used for energy, but that energy is largely used in the process of metabolizing it (in the liver) so that you can excrete it, i.e. NOT used to foster physical activity (like glycogen in your muscles), maintain lean tissues (like amino acids and glycogen in muscles), or support metabolic processes like oxidizing fatty acids. *In my opinion, if weight loss or body composition are your goals, you may be better off obtaining your calories/energy from the macronutrients (protein, carbohydrates, fat) to support your physical activity level and lean tissue mass, instead of taking in calories (from alcohol) that are NOT going to be used for these purposes.
But isn't alcohol considered a carbohydrate?
Many think alcohol is considered a carbohydrate because it is produced from fermentation of carbohydrates like grains or fruits. However, alcohol metabolism actually closely resembles fat metabolism. In this case, the by-products left over after detoxification are converted into fatty acids that can further form triglycerides to be stored in the liver or sent to the peripheral tissues (like being stored in adipose tissue) via lipoproteins like LDL cholesterol. (Nix, 2013) Hence why chronic alcohol intake is associated with fatty liver disease (the first stage of alcoholic liver disease), liver cirrhosis (scarring and damage of the liver tissue), cardiovascular complications (likely associated with increased circulating lipoproteins) including hypertension (high blood pressure), atherosclerosis (plaque formation), stroke, heart attack, as well as type II diabetes, cancer, and more. (Nix, 2013) *This may be one of the reasons why some individuals see a drastic change in body fat/body composition when they decrease or stop their usual drinking behaviors as there would be 1.) a notable decrease in excess fatty acid production 2.) a decrease in non-nutritive calories ('empty calories') with a possible decrease in caloric surplus 3.) an increased ability to absorb nutrients (no longer taking in an 'anti-nutrient' that inhibits nutrient absorption).
About that 'anti-nutrient' thing...
Not only does alcohol by-products of metabolism lead to fatty acid accumulation, the ingestion of alcohol also competes with absorption of other nutrients in the intestine which can be associated with nutrient deficiencies and further down-stream effects. (Gropper and Smith, 2013) Excessive alcohol metabolism is associated with deficiencies in vitamin A, B1, B6, folate, zinc, iron, and many others. (Gropper and Smith, 2013) As if that weren't enough, alcohol is also a depressant (NOT a stimulant like many think) where it can alter neurotransmitter signaling, thought/emotion processing, and it can interfere with medications by slowing down their absorption and by competing for detoxification via the same liver enzyme detoxification systems. (Gropper and Smith, 2013)
Having fun yet? I know, this all sounds like a major buzz-kill.
But isn't red wine supposed to be healthy?
Yes and no. The argument in favor of red wine consumption for a healthy lifestyle is commonly known as the French Paradox (the observation that despite eating high amounts of saturated fats like butter and cheese and drinking wine, the French have some of the lowest trends in cardiovascular disease.) This observation is also seen in the Mediterranean diet where in fact the diet suggests moderate to regular consumption of red wine (1 glass a day) in conjunction with a diet that is high in plant foods and monounsaturated fats (like olive oil) while being low in animal meats, saturated fats, and refined grains. (Nix, 2013)
Let's break down this theory behind red wine:
We know that alcohol is NOT essential to the body (is actually seen as a toxin), provides NO nutrients, and is metabolized in a way that increases fatty acid and triglyceride formation. (All of these would INCREASE risk for adverse health effects and cardiovascular disease.) So maybe it's not the ALCOHOL in the wine, but rather the antioxidants in red wine...
The antioxidant content (specifically resveratrol, a polyphenol) of red wine is suggested to decrease pro-oxidative cell damage, improve nitric oxide availability (vasodilation), and possibly decrease inflammation. (Bonnefont-Rousselot, 2016) HOWEVER: those antioxidants (like resveratrol) found in red wine are NOT specifically associated with the alcohol in the wine, but from the grapes (i.e. the actual carbohydrate that was fermented into the alcohol). In fact, you can get the same antioxidant content from red wine through whole foods like fruits, vegetables, nuts/seeds, whole grains, etc in your normal diet. What should be noted however is that some studies that have found beneficial effects from high doses of resveratrol were in in vitro studies (NOT human studies). (Bonnefont-Rousselot, 2016) As well, the human trials that did show associations with high doses of resveratrol for cardiovascular effects were based on supplements, NOT on wine consumption. (Bonnefont-Rousselot, 2016) In fact, the studies where wine was used as the source of resveratrol showed inconsistent and conflicting findings where for example the actual plasma level of free resveratrol was much lower from wine consumption than the physiologically relevant amounts from the trials with high dose supplements, noting no significant association between the wine drinking and cardiovascular benefits. (Bonnefont-Rousselot, 2016) *In regards to potential antioxidant benefits, there is nothing special about the alcoholic drink (red wine) that you can't obtain from whole foods already (or a non-alcoholic drink like grape juice).
But some studies show trends of health benefits with low to moderate alcohol intake:
What is interesting is that in some of these human trials, it is suggested that low to moderate intake (~1 drink/day) may appear to be beneficial for health based on overall patterns of dietary intake with health parameters like risk of diabetes. (Bonnefont-Rousselot, 2016) Some study findings suggest that low to moderate intake of alcohol may show a beneficial effect on blood glucose concentrations and insulin signaling (possibly prevent type II diabetes), but where this association changes with increased amounts. (Lee, et al. 2017) As a point of reference, the current RDA guidelines suggest that if you are to drink, that 1 drink a day for women, or 2 drinks a day for men, can be considered a part of a healthy diet. (Nix, 2013)*1 drink is considered 14g of alcohol, or 1.5oz (~1 shot) of liquor/12oz beer/5oz (~1glass) wine.
Note the RDA guidelines (14g/day can be considered part of a healthy diet), where these study findings suggest that >30g/day (more than 2 drinks a day) was associated with an increased risk for diabetes, but where light to moderate (5-30g/day, or >1-2 drinks a day) was associated with reduced risk for type II diabetes in a 12 year study of a sample of men (according to a food frequency questionnaire administered over 12 years). (Lee, et al. 2017) It's important to note: these TRENDS may likely be due to the overall lifestyle behaviors that tend to coincide with a pattern of ~1 drink/day like choosing specific food+wine or food+beer pairings. In this sense, the individuals are likely to be more conscientious of what they are eating and their general lifestyle behaviors, as opposed to drinking for sport. (An individual who drinks a glass of red wine a day because they believe it is healthy is ALSO likely to partake in other behaviors that may promote health. Thus a TREND forms between diet and lifestyle with health parameters, but NOT a direct link or causation.)
In contrast to these findings, there are other studies to suggest that even low to moderate consumption of alcohol can increase risk for cancer where men who also smoke showed the strongest association with alcohol intake and cancer risk, but interestingly where women showed this association regardless of smoking behaviors. (Cao, et al. 2015) This last point means that in this sample of women, regardless of whether or not they smoke, the intake of even low to moderate amounts of alcohol was associated with an increased risk for cancer. (Cao, et al. 2015) What's more is that the increased cancer risk for women with alcohol intake was specific for breast cancer, which could be due to increased estrogen associated with alcohol intake. (Cao, et al. 2015) Take note: the alcohol dosages used in this study were 1 drink for women, and 2 drinks for men: the same as the RDA guidelines suggests, yet even this 'low to moderate' amount was associated with increased risk for cancers. (Cao, et al. 2015) *These amounts are not specific to intake every day, but rather average for the week: so a woman drinking 7+ drinks within a week could be deemed 1 drink/day or all 7 drinks on one day.
But you like to drink because it helps you relax and unwind, right?
To each his own. If overall diet and lifestyle are kept in check, there is no reason why a low to moderate amount of alcohol can't be a part of an otherwise healthy lifestyle.
*It's when:
Diet and lifestyle factors are NOT controlled for
OR alcohol intake is excessive to the point of toxicity
OR calories from alcohol are the primary source of calories (like having a 'liquid lunch/dinner' instead of food, i.e. LACK of nutrition)
OR calories from alcohol are being added to your total intake (creating a calorie surplus)
If under these circumstances, then it is suggested that health issues should take precedence and good judgement should be used in deciding whether or not to abstain or partake.
But if athletic performance is your primary goal:
Alcohol can be one sure-fire way to decrease athletic performance as again, it is a priority fuel and thus the body works to metabolize it before anything else which can deter appropriate fuel metabolism and recovery processes in a physically active individual. It should come as no surprise that alcohol intake before activity will decrease athletic ability, largely due to the effects on the central nervous system. (Barnes, 2014) However most individuals would likely not consume alcohol before physical activity, but rather after physical activity, to where the potential negative impacts of alcohol on athletic performance can be due to a range of effects. (Barnes, 2014) The most notable association with decreased athletic performance and alcohol intake is due to a diminished ability to recover, largely associated with disrupted sleep patterns and hormonal disturbances. (Barnes, 2014)
There are findings to suggest that alcohol intake can impair immunoendocrine function, protein synthesis and blood flow and possibly rehydration and glycogen resynthesis, all of which would play a role in decreasing athletic performance. (Barnes, 2014) Factors like incomplete rehydration and glycogen replenishment post-exercise due to alcohol consumption (think of going out for drinks after a workout/competition where alcohol is taken in INSTEAD OF appropriate fuels) are associated with these negative effects on metabolic recovery and indirect effects on soft tissue repair. (Barnes, 2014) I had noted in a previous post about the importance of allowing for the natural inflammatory processes to take effect post-exercise in order for tissues to repair (and thus gain a benefit from the workout). Acute alcohol intake however disrupts this necessary inflammatory process (acts as an anti-inflammatory agent) and can therefore delay the recovery process. (Barnes, 2014) Chronic alcohol intake can further impair the immune system functioning leaving the individual susceptible to illness and immunosuppression. (Barnes, 2014)
When it comes to endocrine (hormone) functioning, study findings suggest that alcohol intake is associated with:
Increased:
cortisol
insulin
dopamine
estrogen
adrenaline
Decreased:
human growth hormone
testosterone
luteinizing hormone
serotonin
melatonin
vasopressin
This basically means that anabolic hormones (responsible for rebuilding and repairing tissues like human growth hormone and testosterone) are negatively impacted by acute alcohol intake, which can decrease an individual's ability to resynthesize tissues during the recovery process. (Barnes, 2014) As well, catabolic hormones like cortisol and adrenaline (epinephrine) are increased which can also impair tissue rebuilding and muscle protein synthesis. (Barnes, 2014) The decrease in vasopressin (anti-diuretic hormone) can impair an individual's ability to properly rehydrate, of which can play a role in decreasing athletic performance. (Barnes, 2014) [Vasopressin is secreted from the posterior pituitary in the brain to help retain water and sodium in the kidneys in order to rehydrate, but a decrease in vasopressin response would allow for water and salt removal from the body. This is a healthy way that the body can effectively eliminate the alcohol by-products (increased diuresis/urination) but it can be problematic if you are already dehydrated, like from physical activity.] Study findings showed that in a sample of males, a decrease in HGH and testosterone associated with acute large doses (1.5g/kg BW or 4oz in a 180lb male) may be detrimental to maintaining and building lean muscle mass while the increase in estrogen can possibly further impact muscle protein synthesis. (Barnes, 2014) *Take note: these findings are based on ACUTE alcohol intake, not chronic long-term ingestion, where for example 1.5g/kg BW is the same as 4oz or ~3-4 shots of liquor for a 180lb male, associated with exhibiting these hormonal effects.
When it comes to sleep disruption, alcohol can decrease the amount of time it takes to fall asleep, but it also decreases the TOTAL amount of time spent in deep sleep. (Barnes, 2014) This means that you may fall asleep faster, but you will spend less total time sleeping and less time in deep sleep (less quality sleep) which may notably be due to the decreases in serotonin and melatonin associated with acute alcohol intake. (Barnes, 2014) This can have indirect negative effects on athletic performance, injury rehabilitation, as well as body composition, as it is during sleep that most recovery processes (like tissue rebuilding) take place. (Barnes, 2014)
Big takeaway here: drink responsibly.
Take into account what your goals are, whatever they may be, whether it's health-related, body composition, athletic performance, or taking advantage of the open bar at your friend's wedding.
Cheers!
References:
Barnes M. Alcohol: Impact on Sports Performance and Recovery in Male Athletes. Sports Medicine. 2014; 44(7):909-919. https://link-springer-com.proxy.lib.fsu.edu/article/10.1007%2Fs40279-014-0192-8
Bonnet-Rousselot D. Resveratol and Cardiovascular Diseases. Nutrients. 2016; 8(5):250. https://www-ncbi-nlm-nih-gov.proxy.lib.fsu.edu/pmc/articles/PMC4882663/
Cao Y, Willett W, Rimm E, et al. Light to moderate intake of alcohol, drinking patterns, and risk of cancer: results from two prospective US cohort studies. British Medical Journal. 2015; https://www-ncbi-nlm-nih-gov.proxy.lib.fsu.edu/pmc/articles/PMC4540790/
Gropper S, Smith J. Advanced Nutrition and Human Metabolism. 6th edition. Wadsworth-Cengage Learning. 2013.
Lee D, Yoo M, Kim H, et al. Association between alcohol consumption pattern and the incidence of risk of type II diabetes in Korean men: A 12 year follow up study. Scientific Reports. 2017; 7(1): 7322. https://www-ncbi-nlm-nih-gov.proxy.lib.fsu.edu/pmc/articles/PMC5544746/
Nix S. Williams' Basic Nutrition and Diet Therapy. 14th edition. Elsevier-Mosby. St. Louis, MO. 2013.