School of Physical Education, Sport & Exercise Sciences, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
Department of Human Nutrition, University of Otago, PO Box 56, Dunedin 9054, New Zealand.
Growth Horm IGF Res. 2020 Dec;55:101353. doi: 10.1016/j.ghir.2020.101353. Epub 2020 Sep 24.
Insulin-like growth factor-I (IGF-1) is an anabolic hormone that stimulates cell growth and division. The effects of IGF-1 may be beneficial (muscle growth/repair) or detrimental (increased risk of several types of cancer and mortality) for health. Dietary protein and physical activity are thought to be factors that modulate IGF-1.
This study analysed the relationships dietary protein vs IGF-1 and physical activity vs IGF-1 independently with a large sample size, and determined if/how physical activity affected the association between dietary protein and IGF-1 in healthy adults.
Regression models were used to assess the association between dietary protein and/or physical activity on serum IGF-1 in a cross-sectional sample of 60,677 healthy adults that were enrolled in the UK Biobank project.
Dietary protein was positively associated with IGF-1 (0.030 nmol/L;95%CI 0.027-0.033;p < 0.001). Individuals undertaking 10-50 excess MET h/week of physical activity had 0.129 nmol/L greater IGF-1 than participants completing less than 10 excess MET h/week (95%CI 0.028-0.230). The "high" category of physical activity (>50 excess MET h/week) was not correlated with IGF-1 (-0.055 nmol/L;95%CI -0.185-0.076). When dietary protein and physical activity were included in the same model, physical activity did not change the relationship between dietary protein and IGF-1, nor visa-versa.
The positive association between dietary protein and IGF-1 was not influenced by physical activity. The former association was stronger than the latter. Thus, when seeking to adjust IGF-1 for possible health concerns, regulating dietary protein may be more pertinent than physical activity as a primary intervention.
胰岛素样生长因子-I（IGF-1）是一种合成代谢激素，可刺激细胞生长和分裂。IGF-1 的作用可能对健康有益（肌肉生长/修复），也可能有害（增加多种癌症和死亡率的风险）。饮食蛋白和身体活动被认为是调节 IGF-1 的因素。
本研究分析了饮食蛋白与 IGF-1 之间的关系以及身体活动与 IGF-1 之间的关系，样本量较大，并确定身体活动是否以及如何影响健康成年人饮食蛋白与 IGF-1 之间的关联。
使用回归模型评估了横断面样本中 60677 名健康成年人中饮食蛋白和/或身体活动与血清 IGF-1 之间的关联，这些成年人参加了英国生物银行项目。
饮食蛋白与 IGF-1 呈正相关（0.030 nmol/L；95%CI 0.027-0.033；p < 0.001）。每周进行 10-50 个额外代谢当量小时的身体活动的个体比每周完成少于 10 个额外代谢当量小时的个体 IGF-1 高 0.129 nmol/L（95%CI 0.028-0.230）。“高”运动量类别（>50 个额外代谢当量小时/周）与 IGF-1 不相关（-0.055 nmol/L；95%CI -0.185-0.076）。当饮食蛋白和身体活动同时包含在同一个模型中时，身体活动并没有改变饮食蛋白与 IGF-1 之间的关系，反之亦然。
饮食蛋白与 IGF-1 之间的正相关关系不受身体活动的影响。前者的关联比后者更强。因此，当试图调整 IGF-1 以应对可能的健康问题时，调节饮食蛋白可能比身体活动作为主要干预措施更为重要。
