Researchers say a "Venus" figurine discovered in 2008 in southern Germany and created an estimated 35,000 years ago may be the oldest statue ever found. Its sexually suggestive figure— large breasts, large rear end—is said to connote fertility. But it also looks extremely fat. Were there obese people in prehistoric times?

    Few, if any. Obesity is defined as having a body mass index higher than 30—the equivalent of being about 5-foot-11 and 220 pounds. The best indicator of body type among prehistoric peoples is present-day societies with a similar lifestyle—that is, hunter-gatherers. From the San people of Botswana to the PygmiesBatek of Malaysia, groups that fall into this category tend to be small and extremely thin. The Baka of Cameroon, for example, are about 5 feet tall and weigh around 105 pounds, giving them an average BMI of 20. Hunter-gatherers are usually thin because they subsist largely on fruits and vegetables, underground tubers, and, in some regions of Africa, honey. They also get calories from animal meat, and some of their diets are especially fish-heavy. But many tribes insist on distributing the meat evenly among the group, so there's rarely enough for one person to get fat on. Hunter-gatherer tribes also stay thin, unsurprisingly, due to a generally active way of life.

    Fossils are of little use in determining the relative fitness of Stone Age humans because, for the most part, the bones of a 150-pound man look similar to the bones of a 250-pound man of the same height. Many old bones do have stress fractures or signs of arthritis, but it's hard to conclude that these indications of degradation are due to obesity. Neanderthals 200,000 years ago were shorter and stockier than we are now, but, again, there's no evidence that they were obese.

    Obesity likely began with the advent of agriculture 12,000 years ago. Food surpluses and the relatively sedentary lifestyle on settlements made overconsumption possible for the first time in human history. Another factor was the rise of processed foods and, with the invention of the steel roller mill in the late 19th century, the possibility of mass-marketing those foods. Grains and other carbohydrates that have been broken down are easier to digest. As a result, you get hungry again faster. Some scientists also theorize that people weighed less in earlier eras because they were exposed to more infections. (If you're eating carrots out of the ground—as opposed to a sealed plastic bag—you're likely to have constant minor parasitic infections.) When you're fighting an infection, your body temperature rises, and you burn more calories.

    Some women in hunter-gathering societies do have abnormally large buttocks, a condition called steatopygia. It's especially common among the Khoisan in southern Africa and tribes in the Andaman Islands. It is sometimes considered a sign of beauty, and may have inspired some of the more voluptuous ancient figurines. The most famous example of steatopygia was the Hottentot Venus, a Khoikhoi woman whose physical characteristics made her a sideshow sensation in 19th-century Europe.

    2008年，在德国南部发现了一尊“维纳斯"的雕像。这尊雕塑如果确实如研究者声称雕刻于35,000年前，那么她将是世界上已发掘的最早的雕像。丰满的乳房、硕大的臀部，这些突出的性征据说是生育力强的象征。但是，她看起来也确实很肥。那么，在史前时期，是否存在肥胖的人？

    即使有，也是极少数的。肥胖指的是体重指数高于30的，比如说，170cm的人却有220磅（相当于99.7903KG）。史前人类身体的各项指数与现在社会中的采猎者（hunter-gaterers）这类人的指数相近。这一类型的人，不论是圣博茨瓦那人（San people of Botswana），还是马来西来的俾格米人（Pygmies Batek），他们都很矮小并且非常地精瘦。又比如，身高152.4cm、体重47.7kg的咔麦隆的巴卡（The Baka of Cameroon）人，他们体重的平均指数只有20。采集者之所以比较瘦是因为他们大多靠水果、蔬菜、地下块茎状植物维持生命，非洲一些地区也会采食蜂蜜。他们也会吃动物的肉来获取能量，有些人更是以鱼为主食。但更多的部落仍坚持肉要均分，因此每一个人得到的肉的份量很难让他胖起来。另外，采猎部落的人一直长不胖的另一个可想而知的原因即是他们总是为了生存忙个不停。

    我们无法依靠化石来断定石器时代人类的身体比例。因为在大多数情况下，如果身高相同，一个150磅（约68Kg）的人和骨架和一个250磅（约 113.4Kg）看起来差不多。虽然很多原始人的骨骼被检测出有骨折或者是关节炎的症状，但这些退化的迹象并不能得出它们是肥胖所致的这一结论。同样，虽然200,000万年前的尼安德特人（Neanderthals）比我们要矮小但却更健壮结实，我们仍没有证据证明他们会患肥胖症。

    肥胖症可能是随着12,000年前农业社会的到来而出现的。食物的富余和相对稳定不变的定居生活，这为人类历史上第一次过度消费提供了可能性。另一个原因是加工食品的增多，并且，由于19世纪末钢滚轮面粉厂的出现，为这类加工食品的大批量生产提供了条件。谷物以及其它的碳水化合物都被磨碎，从而更容易被消化。于是，你也变得更容易饿了。一些科学家还猜测，早期的人类体重更轻可能也跟他们身处更多的感染疾病的环境有关。（如果你吃的胡萝卜是刚从土里挖出来，而不是保存在一个密封的塑料袋里，那么你便很可能会一直受到微小寄生虫的感染。）当你和这些传染病抗争时，你的体温就会升高，从而消耗掉更多的热量。

    采猎社会里，有些女人的臀部确实可能大得有些不正常，现在称之为臀脂过多（steatopygia）。这在南非的科伊桑人和安达曼群岛的部落中尤为常见。某些时候，这样的身材被视为美丽的象征，并且由此产生了这些更具感官刺激的古代雕像。臀脂过多的著名例子就是霍屯都的维纳斯（Hottentot Venus），这个科伊科伊女人，以她的肉体特征成为了19世纪欧洲的杂耍界的“风云"人物。