咖啡是将烘焙过的咖啡豆磨成粉后制作出来的一种成分复杂的饮品,这些成分有助于其风味、香气和潜在的健康影响。
近年来,大量荟萃性分析和叙事性研究得出一致结论:定期适量饮用咖啡可以延长预期寿命和健康寿命,即便是无咖啡因咖啡也有这种作用[1-12]。
《英国营养学杂志》一项荟萃分析显示,咖啡摄入高与低的全因死亡相对风险为0.86[2];《美国流行病学杂志》显示,每天4杯咖啡可使全因死亡率降低16%[5]。
在开展系统性研究以前,人们大多认为喝咖啡对身体有害,可能会导致冠心病[13]。但世界各地不断有研究发现,适量饮用咖啡不仅对身体无害,反而还能起到保护作用,降低大多数影响寿命的疾病的发生风险和死亡风险。具体如下:
定期喝咖啡可降低心血管疾病的发生风险和死亡风险。
有充分证据表明,定期摄入咖啡可以降低不同心血管疾病的发病率和死亡率,包括高血压[14]、心律失常[15]、动脉粥样硬化[16]、冠心病和中风[17]。
对25项研究进行荟萃分析发现,总体来看,饮用咖啡后患高血压的风险略有降低,其中咖啡摄入量最高的个体患高血压的风险降低了7%,但这种关联因地域而异[18]。研究人员认为,这可能和咖啡摄入量以及遗传因素、咖啡制备方法、引用的咖啡种类、吸烟有关。
咖啡喝的多,2型糖尿病和肥胖的发生风险小。
除高血压外,咖啡还可以减少2型糖尿病[19]和肥胖[20]的发生风险。
一项基于百万参与者和4.5万例2型糖尿病患者的系统评价和荟萃分析显示,与不喝或很少喝咖啡的人相比,每天饮用1~6杯咖啡患糖尿病的相对风险分别为0.92、0.85、0.79、0.75、0.71和0.67。也就是说,随着咖啡摄入量的增加,患糖尿病的风险逐渐降低,而且含咖啡因和不含咖啡因的咖啡都有这种作用[19]。
《营养评论》杂志上发表的研究认为,咖啡对2型糖尿病产生影响的可能机制包括:产热、抗氧化、抗炎作用;腺苷受体信号传导的调节;微生物组含量和多样性[24]。Osama等人则发现,咖啡可能是通过脂联素、瘦素浓度对2型糖尿病产生影响[21]。
常喝咖啡可预防神经系统疾病,偶尔喝却可能加重。
几项荟萃分析的结论显示,经常适量饮用咖啡与患痴呆的风险呈负相关,尤其是阿尔兹海默病[22-25]。但需要注意的是,《阿尔兹海默病杂志》上的一项研究分析了1445名年龄在65-84岁的参与者,发现认知正常的老人增加咖啡摄入量后,患轻度认知障碍(MCI)的可能性更高,而坚持喝咖啡且保持适量则与MCI发病率降低有关[26]。
另外,流行病学研究表明,喝咖啡时帕金森病的发生率较低,得益于咖啡的神经保护作用和对肠道微生物组成的影响[27-29]。
喝点咖啡就能降低呼吸系统疾病的死亡风险。
在关于喝咖啡与全因死亡率和特定原因死亡率的研究中,部分涉及呼吸系统疾病分析的结论显示,适量喝咖啡可以降低呼吸系统疾病的死亡风险[30-33]。
美国一项大型前瞻性队列研究对80多万人进行了约10年随访,在喝普通咖啡和不含咖啡因咖啡的人群中均发现,慢性呼吸系统疾病和肺炎导致的死亡风险显著降低。研究人员分析,咖啡可能是通过增强肺功能来降低死亡风险[32]。
适量喝咖啡能降低某些类型癌症的发病率。
从2016年至今,咖啡被国际癌症研究机构归类为“无法归类的致癌物(3类)”[34],但实际上,越来越多的证据表明摄入适量咖啡与某些类型癌症的发病率呈负相关,例如肝癌[35]、黑色素瘤[36]或结直肠癌[37],并且在一些研究中发现口腔癌/咽癌[38]、肾癌[39]和前列腺癌[40]的风险可能降低。
《英国医学期刊》上的一项研究对16项前瞻性队列研究进行荟萃分析,涉及约5.8万例前列腺癌患者和100多万名队列成员,结果显示,较高的咖啡摄入量可能与较低的前列腺癌风险有关[40]。
喝咖啡除了可以减少上述疾病的发生从而增加预期寿命,还可以通过影响身心行为以延长衰老后的健康寿命,即一个人在某个年龄不受疾病、死亡和机能障碍的影响,有望在健康状态下生活的年数。
一项针对13384名参与者的研究得出结论,相对于实际年龄,喝咖啡较多的个体会表现出更年轻的生理年龄[41]。不过研究者表示,喝咖啡较多的参与者往往是年龄较大的男性非西班牙裔白人、受过高等教育、通常已经结婚、有更好的财务状况,并且不太可能吸烟或过度饮酒。
此外,咖啡对健康寿命的益处还包括以下几点:
让心情变好,提高行为能力。
《精神药理学》期刊和《营养、健康与老龄化杂志》上的研究结果显示,习惯喝咖啡的健康老人往往在摄入咖啡或咖啡因后,会报告自己心情状态得到提升,行为表现也有所改善[42,43]。
预防抑郁症,降低自杀风险。
经常喝咖啡(含咖啡因)对抑郁症的发展具有保护作用:伊朗医科大学对29项研究进行荟萃分析,共涉及42万参与者,结果显示,每天增加240毫升的咖啡摄入量可使抑郁症风险降低4%[44];韩国成均馆大学的研究人员认为,规律和适度的咖啡因摄入,可以减少女性自杀风险和抑郁症,但摄入过多反而可能增加自杀风险[45]。
防止感官衰退,增强感知能力。
定期喝咖啡可以帮助老人维持某些感官功能。广州中山大学联合澳大利亚维多利亚皇家眼耳医院的研究人员利用光学相干断层扫描发现,喝咖啡可能具有神经保护潜力,可增加黄斑视网膜神经纤维厚度,防止视神经退行性病变[46]。《运动障碍》期刊上的研究则显示,在帕金森病患者的一级亲属中,摄入更多咖啡因的人嗅觉功能更强[47]。无论是否含咖啡因,咖啡都会增加对甜味的敏感性和降低对苦味的敏感性,并改变随后的味觉感知[48]。
预防衰弱发生,减少跌倒可能。
较高的咖啡摄入量与更好的身体机能密切相关[49],比如增加步速[50]、减少肌肉减少症的发生[51]、降低身体衰弱几率[52]。
《美国医学主任协会杂志》上的一项研究分析了来自新加坡华人健康研究(SCHS)基线和第三次随访的1.2万余名参与者的数据,参与者在基线时平均年龄为53岁,第三次随访的平均年龄为73岁。研究结果显示,在中国成年人中,中年时多喝咖啡,获得更多的咖啡因,到了晚年,身体更不容易衰弱[52]。
咖啡因是咖啡中最著名的成分,但并不是唯一成分。咖啡中还含有多种多酚化合物,比如绿原酸、阿魏酸和类黄酮,都具有抗氧化特性,可保护细胞免受氧化损伤;以及少量矿物质,如钾、镁和烟酸(维生素B3),但与其他饮食来源相比,这些营养素对总膳食摄入量的贡献较小[53]。而且,咖啡因和绿原酸是降低死亡率、延长健康寿命的主要原因[54]。
从大量研究结论可以看出,咖啡本身是一种健康的饮料,但由于经常会添加大量的调味糖浆、奶油等高糖高热量物质,所带来的不良影响反而抵消甚至了超过了咖啡本身的益处[55]。
至于咖啡中的致癌成分——丙烯酰胺,梅奥医疗国际的Donald Hensrud医生曾表示,咖啡中的丙烯酰胺含量较少,这种物质在大量摄入时是有毒的,但喝咖啡的好处已经超过其风险[56]。
对于有喝咖啡习惯的人来说,偶尔一天不喝可能会出现咖啡因戒断性头痛或疲劳、易怒和难以集中精力等。这是因为咖啡因可以刺激大脑和神经系统,虽有助于缓解头部疼痛,但同时还有一定的成瘾性,通常在戒断几天后就会好转[57]。
此外,《美国临床营养学杂志》上的一项研究显示,在高血压患者中,摄入200~300mg(注:星*克的大杯美式中咖啡因含量约200mg)的咖啡因会导致血压显着增加,并将持续3小时左右;相比之下,喝咖啡2 周似乎不会增加血压,也就是说,习惯性喝咖啡并不会增加心血管事件的发生风险。因此,血压未控制的高血压患者应避免摄入大剂量的咖啡因[14]。
习惯喝咖啡的人,最好在每天中午12点前喝1~3杯咖啡,每杯咖啡含量约150ml。没有喝咖啡习惯的人,不建议贸然开始。
每个人都有自己的咖啡因阈值。大多数人每天可以喝1~2杯咖啡,一旦超量就可能导致紧张、心跳加快、心悸、失眠等问题[55]。不过综合上述研究来看,咖啡摄入量无论在降低疾病风险还是延长寿命上,几乎都在2~3杯/天时获得最大益处。需要补充的是,一杯咖啡约150ml。
另外,喝咖啡的时间也有讲究。今年1月,《欧洲心脏杂志》发表的一项观察性研究发现,在一天中,中午12点之前喝咖啡可能更有利于健康[58]。与不喝咖啡相比,中午之前喝咖啡的人,全因死亡风险降低16%、心血管疾病特定死因风险降低31%,具体时间划定在凌晨4点~上午11点59分。
哈尔滨医科大学的研究人员认为,糖尿病患者可能不适合一大早喝咖啡[59]。研究显示,早上(5:00-8:00)喝咖啡,糖尿病患者全因、心血管疾病、心脏病和糖尿病死亡风险分别增加25%、41%、47%、50%;而8:00-12:00喝咖啡的糖尿病患者,全因、心血管疾病、心脏病死亡风险分别降低20%、21%、30%。
最后提醒,虽然喝咖啡好处很多,但对于本身没有喝咖啡习惯、咖啡因敏感或不爱喝咖啡的人来说,不建议贸然开始,以免遭受不必要的副作用。平时喝太多咖啡的人,也应逐渐减少每日饮用量,将咖啡摄入量控制在1~3杯(150~450ml)即可。
参考资料:
[1] Bhatti SK, O’Keefe JH, Lavie CJ. Coffee and tea: perks for health and longevity? Current Opinion in Clinical Nutrition & Metabolic Care. 2013;16(6):688-697.
[2] Je Y, Giovannucci E. Coffee consumption and total mortality: a meta-analysis of twenty prospective cohort studies. British Journal of Nutrition. 2013;111(7):1162-1173.
[3] Malerba S, Turati F, Galeone C, et al. A meta-analysis of prospective studies of coffee consumption and mortality for all causes, cancers and cardiovascular diseases. European Journal of Epidemiology. 2013;28(7):527-539.
[4] O’Keefe JH, Bhatti SK, Patil HR, DiNicolantonio JJ, Lucan SC, Lavie CJ. Effects of habitual coffee consumption on cardiometabolic disease, cardiovascular health, and All-Cause mortality. Journal of the American College of Cardiology. 2013;62(12):1043-1051.
[5] Crippa A, Discacciati A, Larsson SC, Wolk A, Orsini N. Coffee consumption and mortality from all causes, cardiovascular disease, and cancer: A Dose-Response Meta-Analysis. American Journal of Epidemiology. 2014;180(8):763-775.
[6] Zhao Y, Wu K, Zheng J, Zuo R, Li D. Association of coffee drinking with all-cause mortality: a systematic review and meta-analysis. Public Health Nutrition. 2014;18(7):1282-1291.
[7] Grosso G, Micek A, Godos J, et al. Coffee consumption and risk of all-cause, cardiovascular, and cancer mortality in smokers and non-smokers: a dose-response meta-analysis. European Journal of Epidemiology. 2016;31(12):1191-1205.
[8] Takahashi K, Ishigami A. Anti-aging effects of coffee. Aging. 2017;9(8): 1863-1864.
[9] Kim Y, Je Y, Giovannucci E. Coffee consumption and all-cause and cause-specific mortality: a meta-analysis by potential modifiers. European Journal of Epidemiology. 2019;34(8):731-752.
[10] Li Q, Liu Y, Sun X, et al. Caffeinated and decaffeinated coffee consumption and risk of all‐cause mortality: a dose–response meta‐analysis of cohort studies. Journal of Human Nutrition and Dietetics. 2019;32(3):279-287.
[11] Di Maso M, Boffetta P, Negri E, La Vecchia C, Bravi F. Caffeinated coffee Consumption and Health Outcomes in the US population: A Dose–Response Meta-Analysis and Estimation of disease cases and deaths Avoided. Advances in Nutrition. 2021;12(4):1160-1176.
[12] Shin S, Lee JE, Loftfield E, et al. Coffee and tea consumption and mortality from all causes, cardiovascular disease and cancer: a pooled analysis of prospective studies from the Asia Cohort Consortium. International Journal of Epidemiology. 2021;51(2):626-640.
[13] Paul O, Lepper MH, Phelan WH, et al. A longitudinal study of coronary heart disease. Circulation. 1963;28(1):20-31.
[14] Mesas AE, Leon-Muñoz LM, Rodriguez-Artalejo F, Lopez-Garcia E. The effect of coffee on blood pressure and cardiovascular disease in hypertensive individuals: a systematic review and meta-analysis. American Journal of Clinical Nutrition. 2011;94(4):1113-1126.
[15] Bazal P, Gea A, Navarro AM, et al. Caffeinated coffee consumption and risk of atrial fibrillation in two Spanish cohorts. European Journal of Preventive Cardiology. 2020;28(6):648-657.
[16] Surma S, Sahebkar A, Banach M. Coffee or tea: Anti-inflammatory properties in the context of atherosclerotic cardiovascular disease prevention. Pharmacological Research. 2022;187:106596.
[17] Ding M, Bhupathiraju SN, Satija A, Van Dam RM, Hu FB. Long-Term coffee consumption and risk of cardiovascular disease. Circulation. 2013;129(6):643-659.
[18] Haghighatdoost F, Hajihashemi P, De Sousa Romeiro AM, et al. Coffee Consumption and Risk of Hypertension in Adults: Systematic Review and Meta-Analysis. Nutrients. 2023;15(13):3060.
[19] Ding M, Bhupathiraju SN, Chen M, Van Dam RM, Hu FB. Caffeinated and Decaffeinated coffee Consumption and Risk of Type 2 Diabetes: A Systematic Review and a Dose-Response Meta-analysis. Diabetes Care. 2014;37(2):569-586.
[20] Lee A, Lim W, Kim S, et al. Coffee Intake and Obesity: A Meta-Analysis. Nutrients. 2019;11(6):1274.
[21] Osama H, Abdelrahman MA, Madney YM, Harb HS, Saeed H, Abdelrahim MEA. Coffee and type 2 diabetes risk: Is the association mediated by adiponectin, leptin, c‐reactive protein or Interleukin‐6? A systematic review and meta‐analysis. International Journal of Clinical Practice. 2021;75(6).
[22] Nila IS, Moran VMV, Khan ZA, Hong Y. Effect of daily coffee consumption on the risk of Alzheimer’s Disease: A Systematic Review and Meta-Analysis. Journal of Lifestyle Medicine. 2023;13(2):83-89.
[23] Wu L, Sun D, He Y. Coffee intake and the incident risk of cognitive disorders: A dose–response meta-analysis of nine prospective cohort studies. Clinical Nutrition. 2016;36(3):730-736.
[24] Zhu Y, Hu CX, Liu X, Zhu RX, Wang BQ. Moderate coffee or tea consumption decreased the risk of cognitive disorders: an updated dose–response meta-analysis. Nutrition Reviews. 2023;82(6):738-748.
[25] Liu QP, Wu YF, Cheng HY, et al. Habitual coffee consumption and risk of cognitive decline/dementia: A systematic review and meta-analysis of prospective cohort studies. Nutrition. 2016;32(6):628-636.
[26] Solfrizzi V, Panza F, Imbimbo BP, et al. Coffee consumption habits and the risk of mild cognitive impairment: The Italian Longitudinal Study on Aging. Journal of Alzheimer S Disease. 2015;47(4):889-899.
[27] Asuku AO, Ayinla MT, Olajide TS, et al. Coffee and Parkinson’s disease. Progress in Brain Research. January 2024:1-19.
[28] Hong SW, Page R, Truman P. Smoking, coffee intake, and Parkinson’s disease: potential protective mechanisms and components. NeuroToxicology. December 2024.
[29] Zhang T, Song J, Shen Z, et al. Associations Between Different Coffee Types, Neurodegenerative Diseases, and Related Mortality: Findings from a Large Prospective Cohort Study. American Journal of Clinical Nutrition. 2024;120(4): 918-926.
[30] Abe SK, Saito E, Sawada N, et al. Coffee consumption and mortality in Japanese men and women: A pooled analysis of eight population-based cohort studies in Japan (Japan Cohort Consortium). Preventive Medicine. 2019;123:270-277.
[31] Freedman ND, Park Y, Abnet CC, Hollenbeck AR, Sinha R. Association of Coffee Drinking with Total and Cause-Specific Mortality. New England Journal of Medicine. 2012;366(20):1891-1904.
[32] Loftfield E, Freedman ND, Graubard BI, et al. Association of coffee consumption with overall and Cause-Specific mortality in a large US prospective cohort study. American Journal of Epidemiology. November 2015:kwv146.
[33] Saito E, Inoue M, Sawada N, et al. Association of coffee intake with total and cause-specific mortality in a Japanese population: the Japan Public Health Center–based Prospective Study. American Journal of Clinical Nutrition. 2015;101(5):1029-1037.
[34] 致癌物清单新增:咖啡和65℃以上热饮 - 丁香园.
[35] Bhurwal A, Ratta P, Yoshitake S, et al. Inverse Association of Coffee with Liver Cancer Development: An Updated Systematic Review and Meta-analysis. Journal of Gastrointestinal and Liver Diseases. August 2020.
[36] Micek A, Godos J, Lafranconi A, Marranzano M, Pajak A. Caffeinated and decaffeinated coffee consumption and melanoma risk: a dose-response meta-analysis of prospective cohort studies. International Journal of Food Sciences and Nutrition. 2017;69(4):417-426.
[37] Wang Y, Chen J, Zhao R, et al. Dose–response meta-analysis of coffee consumption and risk of colorectal adenoma. European Journal of Clinical Nutrition. 2019;74(2):297-306.
[38] Wang A, Wang S, Zhu C, et al. Coffee and cancer risk: A meta-analysis of prospective observational studies. Scientific Reports. 2016;6(1).
[39] Rhee J, Lim RK, Purdue MP. Coffee consumption and risk of renal cancer: a meta-analysis of cohort evidence. Cancer Causes & Control. 2021;33(1):101-108.
[40] Chen X, Zhao Y, Tao Z, Wang K. Coffee consumption and risk of prostate cancer: a systematic review and meta-analysis. BMJ Open. 2021;11(2):e038902.
[41] Chen X, Yin X, Gao Y, Chen X, Ye N, He X. From cup to clock: exploring coffee’s role in slowing down biological aging. Food & Function. 2024;15(10): 5655-5663.
[42] Cropley V, Croft R, Silber B, et al. Does coffee enriched with chlorogenic acids improve mood and cognition after acute administration in healthy elderly? A pilot study. Psychopharmacology. 2011;219(3):737-749.
[43] Duncan MJ, Clarke ND, Tallis J, Guimarães-Ferreira L, Wright SL. The effect of caffeine ingestion on functional performance in older adults. The Journal of Nutrition Health & Aging. 2014;18(10):883-887.
[44] Torabynasab K, Shahinfar H, Payandeh N, Jazayeri S. Association between dietary caffeine, coffee, and tea consumption and depressive symptoms in adults: A systematic review and dose-response meta-analysis of observational studies. Frontiers in Nutrition. 2023;10.
[45] Park H, Suh BS, Lee K. Relationship between daily coffee intake and suicidal ideation. Journal of Affective Disorders. 2019;256:468-472.
[46] Yuan Y, Bulloch G, Zhang S, et al. Consumption of Coffee and Tea Is Associated with Macular Retinal Nerve Fiber Layer Thickness: Results from the UK Biobank. Nutrients. 2023;15(5):1196.
[47] Siderowf A, Jennings D, Connolly J, Doty RL, Marek K, Stern MB. Risk factors for Parkinson’s disease and impaired olfaction in relatives of patients with Parkinson’s disease. Movement Disorders. 2007;22(15):2249-2255.
[48] Fjaeldstad AW, Fernandes HM. Chemosensory Sensitivity after Coffee Consumption Is Not Static: Short-Term Effects on Gustatory and Olfactory Sensitivity. Foods. 2020;9(4):493.
[49] Mazeaud S, Castellana F, Coelho-Junior H, et al. Coffee drinking and Adverse Physical Outcomes in the aging Adult Population: a Systematic review. Metabolites. 2022;12(7):654.
[50] Jyväkorpi SK, Urtamo A, Kivimäki M, Strandberg TE. Associations of coffee drinking with physical performance in the oldest-old community-dwelling men The Helsinki Businessmen Study (HBS). Aging Clinical and Experimental Research. 2020;33(5):1371-1375.
[51] Lee DY, Shin S. Sarcopenic obesity is associated with coffee intake in elderly Koreans. Frontiers in Public Health. 2023;11.
[52] Chua KY, Li H, Lim WS, Koh WP. Consumption of coffee, tea, and caffeine at midlife, and the risk of physical frailty in late life. Journal of the American Medical Directors Association. 2023;24(11):1655-1662.e3.
[53] Mattioli AV, Farinetti A. The beneficial effects of coffee consumption: Beyond facial skin aging. Journal of Cosmetic Dermatology. September 2024.
[54] Lopes CR, Cunha RA. Impact of coffee intake on human aging: Epidemiology and cellular mechanisms. Ageing Research Reviews. 2024;102:102581.
[55] Kathleen M. Zelman. The buzz on coffee. WebMD. Published May 6, 2008.
[56] Williams V. Mayo Clinic Minute: Filtering coffee facts from fiction. Mayo Clinic News Network. Published March 4, 2022.
[57] Caffeine: How much is too much? Mayo Clinic. Published March 19, 2022.
[58] Wang X, Ma H, Sun Q, et al. Coffee drinking timing and mortality in US adults. European Heart Journal. January 2025.
[59] Yang R, Lei Q, Liu Z, et al. Relationship between timing of coffee and tea consumption with mortality (total, cardiovascular disease and diabetes) in people with diabetes: the U.S. National Health and Nutrition Examination Survey, 2003–2014. BMC Medicine. 2024;22(1).