So far in this blog, I’ve presented current research showing positive associations between moderate wine consumption and better cognitive function/memory, as well as cardiovascular protective effects. I’ve also presented some negative associations between alcohol/wine consumption and In Vitro Fertilization success.
In today’s post, I’ll present results from a study performed in 2009 (which was the first of its’ kind) looking at the effect of alcohol consumption on bone mineral density (BMD) in older men and women. The results of this study could have implications for osteoporosis risk and whether specific types of alcohol result in increased or decreased BMD.
To date, studies have shown that there is a positive association between alcohol consumption and bone mineral density (BMD) in older women. However, little work has been done focusing on men, or younger women. In the few studies that have been done, it has been found that for men aged 65 years and older, there was a linear relationship between alcohol consumption and BMD at the hip and spine, and that greater alcohol consumption was not related to fracture risk. Another study found that for both men and women aged 20 years and older, BMD at the hip and femoral neck was much higher in men consuming greater than 5 drinks per month (compared to non-drinkers). The same study found that for post-menopausal women consuming greater than 29 drinks per month (nearly one per day) had a higher femoral neck BMD that non-drinkers.
Somewhat contrary to these results, other studies have shown a more U-shaped relationship between alcohol consumption and risk of a hip fracture in adults over 65 years old. The study found positive effects with alcohol consumption of up to 2 drinks per day, but negative effects (or increased risk of fractures) with consumption greater than 2 drinks per day. The authors of these studies suggested that there could be differences between alcohol types, and also between age and sex.
At the time of publication, no other study had examined whether are different effects between specific types of alcohol (beer, wine, or liquor) and bone mineral density are present, or if all alcohol behaves in similar ways regarding BMD. Wine has been shown to have several important health benefits, when consumed in moderation, and beer has been shown to be a significant source of silicon (which also has health benefits), which could contribute to their effectiveness on increasing BMD in older adults. The current study under review examines the association between total alcohol consumption and individual types of alcoholic beverages on bone mineral density in older men, postmenopausal women, and premenopausal women.
The individuals in the study were participants in the Framingham Osteoporosis Study, and returned every 4 years for a physical exam and to complete several questionnaires and tests. In the subsequent 5th and 6th visits, bone mineral density was measured for all participants. There were a total of 2,919 individual participants, 1280 of them men, and 1639 of them women, all between the ages of 29-86 years old.
Alcohol consumption was measured as an average between the two questionnaires given in the 5th and 6th visits. Bone mineral density was measured via dual-energy X-ray absorptiometry at the right hip (broken down into total hip, trochanter, and femoral neck), and at the lumbar spine. Dietary history was measured via questionnaires (as with alcohol consumption). Individuals were identified as either being “former drinkers” or “never drinkers”, to help tease out any effect past drinking may have on bone mineral density.
Confounding factors taken into consideration during this study were: menopausal status, physical activity level, smoking status, medication use, estrogen use, use of osteoporosis medication, and total intake of energy (dietary calcium, dietary vitamin D, magnesium, potassium, and vitamin K).
For more detailed methods, please reference the article cited at the end of this post, or leave a comment with specific questions.
The average age of men in this study was 61 years old; postmenopausal women had an average age of 62 years old, and premenopausal women had an average age of 48 years old. The average BMI (body mass index) for all of the groups was in the overweight range (27-29). 11-13% of the participants were smokers. Almost no men or premenopausal women were taking osteoporosis medication, though 4.1% of postmenopausal women were taking that type of medication.
The majority of the individuals in the study, according to their questionnaires, were moderate drinkers, with none-1 drink consumed per day (44% men, 56% postmenopausal women, 62% premenopausal women). 21% of men, 7% of postmenopausal women, and 7% of premenopausal women were heavy consumers, drinking more than 2 drinks per day. Men consumed primarily beer, while women consumed primarily wine. For wine drinkers, most consumed both red and white wine. For men, this break down was about 50/50 for red and white, whereas for women, 75% of the wine consumed was white, while 25% of the wine consumed was red.
The study found a lot of significant relationships between bone mass density and alcohol consumption, of which I will present to you in bullet format, for easier reading.
· In men: Nondrinkers and those drinkers consuming up to ½ a drink per day had significantly lower bone mass density than those drinking 1-2 drinks per day.
· Men consuming more than 2 drinks (beer or liquor, specifically) per day show significantly lower bone mass density compared to the moderate 1-2 drinks per day group.
· These trends for men tended to appear much strong for postmenopausal women.
o For postmenopausal women, those consuming 2 or more drinks per day showed significantly higher bone mineral density than nondrinkers.
o Wine consumption showed significantly higher bone mineral density in all bone sites measured compared to nondrinkers.
o Beer consumption showed significantly higher bone mineral density only at the femoral neck site.
o Liquor consumption showed significantly higher bone mineral density only at the lumbar spine site.
· There was no association between alcohol consumption and bone mineral density of premenopausal women, though there was low power with this test, and no solid conclusion can thereby be made.
· For men: the highest bone mineral density was seen in those consuming 1-2 drinks per day, with lower bone mineral density occurring when consumption was higher.
o Bone mineral density was between 2.5-5.3% greater in men consuming 1-2 alcoholic drinkers per day, compared to nondrinkers.
o Bone mineral density was between 4.5-7% greater in men consuming 1-2 beers per day than non-beer drinkers.
o Bone mineral density was between 3-8.9% lower in men consuming greater than 2 liquor drinks per day, compared to nondrinkers.
· For postmenopausal women: linear trends were more pronounced than with men.
o Bone mineral density was between 5-7.4% greater in postmenopausal women consuming greater than 2 alcoholic drinks per day, compared to nondrinkers.
o Bone mineral density was between 8.3-10.7% greater in postmenopausal women consuming greater than 2 glasses of wine per day, than nondrinkers.
o Bone mineral density was between 7.9% greater (in the spine only) for those postmenopausal women consuming greater than 2 liquor drinks per day, compared to nondrinkers.
What does this all mean?
The results shown in this study indicate that there seems to be protective effects of alcohol, particularly wine and beer, on bone mineral density in adults. There also appears to be a difference in response between different types of alcoholic beverages, and between the sexes. For men, it appears that moderate consumption of beer is beneficial for bone mineral density, however heavier consumption of alcohol tends to have more negative effects on bone mineral density for men (wine not analyzed).
For postmenopausal women, the effect is much different, in that not only is moderate alcohol consumption good for bone mineral density, but it also appears that larger quantities of alcohol consumption are also beneficial in regards to bone mineral density. In postmenopausal women, it appears that wine gives the strongest benefit of increased bone mineral density.
Why there is this difference is response between premenopausal and postmenopausal women is not clear, though the authors of this study speculate that there could be possible effects of alcohol (specifically, the ethanol component) on adrenal androgens or estrogen concentrations. The effect may be seen more in postmenopausal women and men than in premenopausal women since the estrogens levels, which are typically lower in postmenopausal women and men, are increased by the presence of alcohol. The authors also speculated that it is the actual mechanism of increased bone mineral density with alcohol consumption may be an acute suppression of bone resorption, which is the primary cause of bone mineral loss (which has been shown in other studies).
With wine, resveratrol, which is a major constituent of wine and has been shown to have protective cardiovascular effects, may also play a role in this observed increase in bone mineral density in older adults. In the rat model, studies have shown that rats treated with resveratrol had significantly greater bone mineral densities than those rats not treated. So, it is possible that resveratrol, in addition to ethanol and other constituents of wine, may be playing an important role in this relationship between alcohol (specifically, wine) intake and increased bone mineral density.
Whatever the mechanism may be, be it through increase estrogen levels by ethanol intake or decrease bone resorption, it seems to be the cause that moderate alcohol intake (in particular wine for postmenopausal women) has a positive effect on decreasing bone mineral loss, and thereby potentially decreasing the risk of osteoporosis. One must be careful, however, as even though it was shown that postmenopausal women consuming large amounts of alcohol per day had increased bone mineral density, one also has to remember the negative effects of high alcohol intake on other bodily systems.
The authors indicate a few limitations of the study, which could potentially have negative effects on the results shown (though I think it’s likely that the results would not change very significantly), and I believe it’s important to list those for you now, so that you may judge for yourself whether you think the results are reliable:
- Long-term alcohol effects were not taken into consideration, and could be confounding factors in the study.
- Even though bone mineral density was adjusted for the confound factors I listed in the methods section, there could be other factors not included that could also be confounding.
- A steady drinking pattern may be more beneficial than binge drinking, though because of the nature of the questionnaires, and the fact that alcohol consumption was measured as an average and not a daily usage, some misclassification of alcohol consumption patterns could have been made.
- Since the number of women consuming beer was so low, no conclusions could be drawn from it, thereby we won’t know how beneficial (or not) beer is compared to other alcoholic beverages.
More work needs to be done to help tease out some of the details, however, I think it is clear from this study that moderate consumption of alcohol, particular wine, has positive health benefits related to increase bone mineral density, and thereby potentially decreased risk of osteoporosis in older adults. Though heavy alcohol consumption was also shown to have positive effects on bone mineral density in postmenopausal women, it should be noted that heavy alcohol consumption would have more negative effects in other parts of the body, thus would ultimately be detrimental over all.
For kids, the saying goes: “Milk does a body good”, whereas for older adults (when consumed moderately), I think it’s safe to say that “Wine does a body good”!
For questions/comments/requests for clarifications, please feel free to comment below! I’d love to hear from you!
Full citation for the article under review:
Tucker, K.L., Jugdaohsignh, R., Powell, J.J., Qiao, N., Hannan, M.T., Sripanyakorn, S., Cupples, L.A., and Kiel, D.P. 2009. Effects of beer, wine and liquor intakes on bone mineral density in older men and women. American Journal of Clinical Nutrition 89: 1188-1196.
I am not a health professional, nor do I pretend to be. Please consult your doctor before altering your alcohol consumption habits. Do not consume alcohol if you are under the age of 21. Do not drink and drive. Enjoy responsibly!