人們已經知道心血管疾病和癌症與飽和脂肪的攝入相關。丹麥一項新研究發現，男士攝入的飽和脂肪越多，精子濃度就越低，精子質量也隨之下降。這項研究發表在新一期《美國臨床營養學雜誌》上。
這項研究選取了701名20歲左右的丹麥男子為研究對象。這些研究對象提供他們此前三個月的飲食情況，並提供精液樣本。研究人員按照飽和脂肪攝入情況把他們分成四組，並比較每組的精子數量。
研究人員發現，攝入飽和脂肪的比例與精子濃度、總數“有明顯的關聯”。飽和脂肪占能量攝入比例小於11.2%的人，平均精子濃度為每毫升5000萬，精子總數約為1.63億。而飽和脂肪占能量攝入比例大於15%的人，平均精子濃度為每毫升4500萬個，精子總數為1.28億。
世衛組織規定，男子的精子濃度超過每毫升1500萬才為正常。在這項研究中，攝入脂肪最高的人有18%未達標，而攝入脂肪最低的人群隻有13%。平均而言，攝入脂肪最高的人群精子濃度比攝入脂肪最低的人群低38%，精子總數也少41%。
研究報告的首席作者蒂娜·延森指出，這項研究雖未能確定其他生活方式因素是否有影響，但可以解釋男子精子數量持續下降的現象。她說，下一步的研究目標是找出飽和脂肪影響精子數量的機製，從而通過減少飽和脂肪攝入來改善男子精子質量。
法國科學家去年研究發現，35歲左右的法國男子的平均精子濃度從1989年的每毫升7400萬個減少到2005年的每毫升5000萬個，研究人員認為肥胖可能是一個原因。
High dietary intake of saturated fat is associated with reduced semen quality among 701 young Danish men from the general population
Tina K Jensen, Berit L Heitmann, Martin Blomberg Jensen, Thorhallur I Halldorsson, Anna-Maria Andersson, Niels E Skakkeb k, Ulla N Joensen, Mette P Lauritsen, Peter Christiansen, Christine Dalg rd, Tina H Lassen, and Niels J rgensen
Background: Saturated fat intake has been associated with both cardiovascular disease and cancer risk, and a newly published study found an association between saturated fat intake and a lower sperm concentration in infertile men. Objective: The objective was to examine the association between dietary fat intake and semen quality among 701 young Danish men from the general population. Design: In this cross-sectional study, men were recruited when they were examined to determine their fitness for military service from 2008 to 2010. They delivered a semen sample, underwent a physical examination, and answered a questionnaire comprising a quantitative food-frequency questionnaire to assess food and nutrient intakes. Multiple linear regression analyses were performed with semen variables as outcomes and dietary fat intakes as exposure variables, adjusted for confounders. Results: A lower sperm concentration and total sperm count in men with a high intake of saturated fat was found. A significant dose-response association was found, and men in the highest quartile of saturated fat intake had a 38% (95% CI: 0.1%, 61%) lower sperm concentration and a 41% (95% CI: 4%, 64%) lower total sperm count than did men in the lowest quartile. No association between semen quality and intake of other types of fat was found. Conclusions: Our findings are of potentially great public interest, because changes in diet over the past decades may be part of the explanation for the recently reported high frequency of subnormal human sperm counts. A reduction in saturated fat intake may be beneficial for both general and reproductive health.
