Maurel DB, Boisseau N, Benhamou CL, Jaffre C. Alcohol and bone: review of dose effects and mechanisms. Osteoporos Int (2012) 23:1–16; DOI 10.1007/s00198-011-1787-7
Alcohol is widely consumed across the world. It is consumed in both social and cultural settings. Until recently, two types of alcohol consumption were recognized: heavy chronic alcohol consumption or light consumption. Today, there is a new pattern of consumption among teenagers and young adults namely: binge drinking.
Heavy alcohol consumption is detrimental to many organs and tissues, including bones, and is known to induce secondary osteoporosis. Some studies, however, have reported benefits from light alcohol consumption on bone parameters. To date, little is known regarding the effects of binge drinking on bone health. Here, we review the effects of three different means of alcohol consumption: light, heavy, and binge drinking. We also review the detailed literature on the different mechanisms by which alcohol intake may decrease bone mass and strength.
The effects of alcohol on bone are thought to be both direct and indirect. The decrease in bone mass and strength following alcohol consumption is mainly due to a bone remodeling imbalance, with a predominant decrease in bone formation. Recent studies, however, have reported new mechanisms by which alcohol may act on bone remodeling, including osteocyte apoptosis, oxidative stress, and Wnt signalling pathway modulation. The roles of reduced total fat mass, increased lipid content in bone marrow, and a hypoleptinemia are also discussed.
The authors conclude that “Further investigation is necessary as alcohol may change osteocyte function but the effects of alcohol on osteocyte markers and differentiation genes such as Sost are almost unknown, as the impact of alcohol consumption on osteoblast and osteoclast apoptosis. As a public health message, the dose that should serve as a limit for bone health is one glass per day for women and two for men. More than two glasses per day may induce the negative effects of alcohol on bone tissue.”
Osteoporosis and fractures are key problems of the elderly, and the association of alcohol with osteoporosis is an extremely important topic. Unfortunately, in the opinion of the Forum, the paper is confusing, and especially does not answer key questions on the association between moderate drinking and osteoporosis. Forum members believed that a formal meta-analysis or other summary of existing data would have been more helpful.
The authors state that light-moderate drinking may have a desirable effect, but seem to always add a counter argument involving greater alcohol consumption. For example, they state: “While light and moderate alcohol consumption are not associated with increased fracture risks (<27 drinks/week for men and <13 drinks/week for women), a consumption of more than four glasses per day in men and more than two glasses per day for women constitutes a major risk factor for fractures.” As one Forum reviewer stated: “It is difficult to trace the pathways the authors followed from their data to conclusions. They seem to ignore individual variation, yet without statistical armamentarium to do so.” Said another reviewer: “The paper lacks clarity and no straight line of thinking; it is an anecdotal representation of facts chosen without a systematic search method.”
The authors’ definition of levels of alcohol consumption is based only on cut-points of 10 and 30 g/day, with no reference to the pattern of drinking. The paper continually mixes the effects of light drinking with those of abuse. Based on a single study (Ganry et al,1 a large study conducted in France), it makes statements such as “One glass of alcohol has no effect or beneficial effects on bone, regardless of the type of alcohol consumed.” (This is stated even though the Ganry paper concluded: “The detrimental effect of alcohol consumption may occur only above three glasses of wine per day.”1)
The authors of the present paper state that “This data suggests that moderate alcohol consumptions (1–3 glasses per day) may be associated with an increase of bone mineral density in elderly women while it is not the case for men or premenopausal women (>2 glasses). Moreover, it seems that the different type of alcoholic beverages do not have the same effects on bone metabolism. This may be due to the various constituents present in wine and beer such as silicon or polyphenols.” The paper does not, however, explore beverage differences very well in the body of the paper. Most of the paper deals with mechanisms by which heavy chronic alcohol consumption adversely affects bone metabolism.
Mechanisms of alcohol’s effect on bone metabolism: This paper contributes to our understanding of the mechanisms by which the consumption of beer, wine, and spirits may affect osteoporosis (through bone density, bone microarchitecture, bone remodeling, etc.) As a reviewer stated: “I think this is a good overview on the effects of alcohol on bone metabolism. It may be useful in calling attention to osteopenia, which is becomming a major health problem with our aging population.”
Public health policy: Unfortunately, the paper provides little overall assessment that would be useful for setting public health policy. The paper suggests that the only aspect of alcohol consumption that relates to health is the number of glasses or bottles of wine consumed per day, with no mention of the frequency of drinking, with or without food, etc. The authors’ conclusion states: “As a public health message, the dose that should serve as a limit for bone health is one glass per day for women and two for men. More than two glasses per day may induce the negative effects of alcohol on bone tissue.” As stated by a Forum reviewer: “The final statement of the authors referring to public health is unjustified by the data they present. I still agree with the WHO Technical Report Series 916, Geneva 2003, which states that a decrease of the risk of osteoporotic fractures is associated with moderate drinking, at a ‘possible’ evidence level.”
Reference from this paper: 1. Ganry O, Baudoin C, Fardellone P. Effect of alcohol intake on bone mineral density in elderly women: the EPIDOS Study. Epidemiologie de l’Osteoporose. Am J Epidemiol 2000;151:773–780.
Previous Forum comments on alcohol and osteoporosis: Forum reviewers were concerned that the paper tended to disregard a considerable amount of the empirical epidemiologic literature on the subject. In 2011, the Forum prepared a summary of the existing data on this subject in response to the proposed US Dietary Guidelines (See Recent Reviews, Critique 011, on the Forum web-site. In our comments to the Dietary Guidelines committee we stated: “A number of recent prospective studies have confirmed that moderate alcohol consumption is positively associated with bone mineral density (BMD). While studies in the young indicate an increase in the risk of falls above a certain level of intake, most studies in the elderly actually show a lower risk of falls and fractures among moderate drinkers in comparison with non-drinkers (e.g., Felson et al 1995, Macdonald et al 2004, Mukamal et al 2007, Berg et al 2008, Tucker et al 2009).
We continued in our comments: “The special properties of beer might deserve a mention (Sripanyakorn et al 2004). The effect on BMD by silicon is about twice the effect seen with other dietary elements such as calcium. Beer appears to be a major contributor to Si intake. Diets that are high in Si may contribute to beneficial effects on bone which, for moderate beer intake, may be in addition to, or separate from, the effect of ethanol.” The study by Tucker et al from Framingham concluded that “Moderate consumption of alcohol (especially of beer and wine) may be beneficial to bone in men and postmenopausal women.”
References from Forum Critique 011 (www.bu.edu/alcohol-forum) :
Felson DT, Zhang Y, Hannan MT, Kannel WB, Kiel DP. Alcohol intake and bone mineral density in elderly men and women. The Framingham Study. Am J Epidemiol 1995;142:485-492.
Macdonald HM, New SA, Golden MH, Campbell MK, Reid DM. Nutritional associations with bone loss during the menopausal transition: evidence of a beneficial effect of calcium, alcohol, and fruit and vegetable nutrients and of a detrimental effect of fatty acids. Am J Clin Nutr 2004;79:155-165.
Mukamal KJ, Robbins JA, Cauley JA, Kern LM, Siscovick DS. Alcohol consumption, bone density, and hip fracture among older adults: the Cardiovascular Health Study. Osteoporos Int 2007;18:593-602.
Berg KM, et al. Association between alcohol consumption and both osteoporotic fracture and bone density. Am J Med 2008;121:406-418.
Tucker KL, Jugdaohsingh R, Powell JJ, Qiao N, Hannan MT, Sripanyakorn S, Cupples LA, Kiel DP. Effects of beer, wine, and liquor intakes on bone mineral density in older men and women. Am J Clin Nutr 2009;89:1188-1196.
Sripanyakorn S, Jugdaohsingh R, Elliott H, Walker C, Mehta P, Shoukru S, Thompson RP, Powell JJ. The silicon content of beer and its bioavailability in healthy volunteers. Brit J Nutrition 2004;91:403-409.
Osteoporosis is a key underlying factor in fractures among the elderly, which are increasingly a major health problem. A review paper from France on the association between alcohol consumption and bone metabolism states that heavy alcohol intake may adversely affect bone mineral density and increase the risk of osteoporosis. It states that lighter drinking may actually improve bone density, but presents very limited data to support this statement. Forum members were disappointed that the paper did not carry out a meta-analysis or other synthesis of the data; further, data from a number of key epidemiologic studies on the subject were not discussed in the paper.
The paper provides important information on the mechanisms by which alcohol may affect bone metabolism. The authors describe effects of alcoholic beverages on bone density, bone microarchitecture, bone remodeling, and other mechanisms, which help explain how alcohol and polyphenols and other constituents of beer and wine may relate to the risk of fractures in the elderly.
Unfortunately, despite what the authors’ conclude, the paper does not provide a summation of the scientific data upon which public health policy can be based. Overall, current scientific data suggest that bone mineral density and the risk of fractures are favorably affected by light-to-moderate drinking, but adversely affected by heavy drinking and alcoholism.
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Comments on this paper were provided by the following members of the International Scientific Forum on Alcohol Research:
Erik Skovenborg, MD, Scandinavian Medical Alcohol Board, Practitioner, Aarhus, Denmark
R. Curtis Ellison, MD, Section of Preventive Medicine & Epidemiology, Boston University School of Medicine, Boston, MA, USA
Arne Svilaas, MD, PhD, general practice and lipidology, Oslo University Hospital, Oslo, Norway
Harvey Finkel, MD, Hematology/Oncology, Boston University Medical Center, Boston, MA, USA
Francesco Orlandi, MD, Dept. of Gastroenterology, Università degli Studi di Ancona. Italy
David Van Velden, MD, Dept. of Pathology, Stellenbosch University, Stellenbosch, South Africa