School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University.
Sci Prog. 2013;96(Pt 4):319-68. doi: 10.3184/003685013X13743292107915.
How have climate change and diet shaped the evolution of human energy metabolism, and responses to vitamin C, fructose and uric acid? Through the last three millennia observant physicians have noted the association of inappropriate diets with increased incidence of obesity, heart disease, diabetes and cancer, and over the past 300 years doctors in the UK observed that overeating increased the incidence of these diseases. Anthropological studies of the Inuit culture in the mid-nineteenth century revealed that humans can survive and thrive in the virtual absence of dietary carbohydrate. In the 1960s, Cahill revealed the flexibility of human metabolism in response to partial and total starvation and demonstrated that type 2 diabetics were better adapted than healthy subjects to conserving protein during fasting. The potential role for brown adipose tissue thermogenesis in temperature maintenance and dietary calorie control was suggested by Rothwell and Stock from their experiments with 'cafeteria fed rats' in the 1980s. Recent advances in gene array studies and PET scanning support a role for this process in humans. The industrialisation of food processing in the twentieth century has led to increases in palatability and digestibility with a parallel loss of quality leading to overconsumption and the current obesity epidemic. The switch from animal to vegetable fats at the beginning of the twentieth century, followed by the rapid increase in sugar and fructose consumption from 1979 is mirrored by a steep increase in obesity in the 1980s, in the UK and USA. Containment of the obesity epidemic is compounded by the addictive properties of sugar which involve the same dopamine receptors in the pleasure centres of the brain as for cocaine, nicotine and alcohol. Of the many other toxic effects of excessive sugar consumption, immunocompromisation, kidney damage, atherosclerosis, oxidative stress and cancer are highlighted. The WHO and guidelines on sugar consumption include: alternative non-sugar sweeteners; toxic side-effects of aspartame. Stevia and xylitol as healthy sugar replacements; the role of food processing in dietary health; and beneficial effects of resistant starch in natural and processed foods. The rise of maize and soya-based vegetable oils have led to omega-6 fat overload and imbalance in the dietary ratio of omega-3 to omega-6 fats. This has led to toxicity studies with industrial trans fats; investigations on health risks associated with stress and comfort eating; and abdominal obesity. Other factors to consider are: diet, cholesterol and oxidative stress, as well as the new approaches to the chronology of eating and the health benefits of intermittent fasting.
气候变化和饮食如何塑造了人类能量代谢的进化，以及对维生素 C、果糖和尿酸的反应？在过去的三千年里，有观察力的医生注意到，不适当的饮食与肥胖、心脏病、糖尿病和癌症的发病率增加有关，在过去的 300 年里，英国的医生观察到，暴饮暴食会增加这些疾病的发病率。19 世纪中叶对因纽特文化的人类学研究表明，人类可以在几乎没有饮食碳水化合物的情况下生存和茁壮成长。20 世纪 60 年代，卡希尔揭示了人类新陈代谢对部分和完全饥饿的适应性，并证明 2 型糖尿病患者比健康受试者更能在禁食期间保存蛋白质。罗思韦尔和斯托克从 20 世纪 80 年代对“自助餐厅喂养的大鼠”的实验中提出，棕色脂肪组织产热在维持体温和控制膳食热量方面可能发挥作用。近年来，基因阵列研究和正电子发射断层扫描技术的进展支持了这一过程在人类中的作用。20 世纪食品加工工业化导致了适口性和消化率的提高，同时质量下降，导致过度消费和当前的肥胖流行。20 世纪初，动物脂肪向植物脂肪的转变，以及 1979 年以来糖和果糖消费的迅速增加，与英国和美国肥胖率在 20 世纪 80 年代的急剧上升相吻合。肥胖流行的控制因糖的成瘾性而变得复杂，糖的成瘾性涉及大脑愉悦中心与可卡因、尼古丁和酒精相同的多巴胺受体。过量摄入糖的许多其他毒性作用中，免疫功能低下、肾损伤、动脉粥样硬化、氧化应激和癌症被突出强调。世界卫生组织和糖摄入量指南包括：替代非糖甜味剂；阿斯巴甜的毒性副作用。甜菊糖和木糖醇作为健康的糖替代品；食品加工在饮食健康中的作用；以及天然和加工食品中抗性淀粉的有益作用。玉米和大豆基植物油的兴起导致ω-6 脂肪过量和ω-3 与 ω-6 脂肪饮食比例失衡。这导致了对工业反式脂肪的毒性研究；对与压力和舒适饮食相关的健康风险的调查；以及腹部肥胖。其他需要考虑的因素包括：饮食、胆固醇和氧化应激，以及新的饮食时间安排方法和间歇性禁食的健康益处。
