什么是生酮饮食?

什么是生酮饮食?

You've heard of low-carbohydrate, high-protein diets like the Atkins diet and paleo diet. A strict version of those diets has also gained popularity, simply called the ketogenic or keto diet.

你可能听说过低碳水化合物、高蛋白饮食，比如阿特金斯饮食法和旧石器饮食法。这些饮食的严格版本也变得流行起来，简单地称为生酮饮食或酮饮食。

Ketogenic diets are low in carbohydrates and high in fats, a combination that sends your body into a state of ketosis. (Photo: Ronda Kimbrow/Shutterstock)

These ketogenic diets are occasionally popular because they allow people to lose weight quickly, but do you know what, exactly, they do in your body to trigger weight loss?

这些生酮饮食偶尔很受欢迎，因为它们能让人们快速减肥，但你知道它们在你体内引发减肥的确切作用吗?

In a standard carb-loaded American diet, the body burns glucose from carbohydrates as an energy source in a process called glycosis. But when you limit your carbs and increase your fat intake, your body moves into a metabolic state of "ketosis," meaning that it's burning fat stored in your body instead of glucose, according to WebMD. Ketosis also drastically reduces blood sugar and insulin resistance.

在标准的含碳水化合物的美国饮食中，身体燃烧碳水化合物中的葡萄糖作为能量来源，这一过程被称为糖酵解。但是当你限制碳水化合物的摄入量，增加脂肪的摄入量，你的身体就进入了“酮症”的代谢状态，这意味着它燃烧的是储存在你体内的脂肪，而不是葡萄糖。酮症也大大降低了血糖和胰岛素抵抗。

As Dr. Eric Westman, director of the Lifestyle Medicine Clinic at Duke University, told Time magazine, "You determine what your body burns for fuel based on what you feed it."

杜克大学生活方式医学诊所主任埃里克·韦斯特曼博士在接受《时代》杂志采访时表示，“你的身体燃烧什么燃料，取决于你给它吃了什么。”

Possible medical benefits

可能的医疗福利

Ketogenic diets have been used to treat pediatric epilepsy, multiple sclerosis and cancer. (Photo: Elena Shashkina/Shutterstock)

A ketogenic diet has been used for almost 100 years to treat pediatric epilepsy, Scientific American reports, because a ketogenic diet mimics fasting, which has long been known to have a therapeutic effect on seizures. Similar to a state of ketosis, the body also burns fat for energy during fasts. Usually, a pediatric ketogenic diet starts with 24 hours of fasting in a hospital setting, where doctors can monitor frequency of seizures, medication, and help educate the parents on the ins and outs of the diet.

据《科学美国人》报道，生酮饮食用于治疗小儿癫痫已有近100年的历史，因为生酮饮食类似于禁食，而禁食对癫痫发作早有疗效。与酮症类似，身体在禁食期间也会燃烧脂肪来获取能量。通常情况下，儿科生酮饮食从24小时的禁食开始，在医院里，医生可以监测癫痫发作的频率、用药情况，并帮助教育家长了解饮食的来由。

Types of ketogenic diets

生酮饮食的类型

Not all ketogenic diets are the same. They all encourage followers to limit carbohydrates, including breads, sweets, sugary drinks, legumes, fruits and potatoes. Instead, the diets are rich in meats, eggs, cheese, fish, nuts, butter, oils, seeds and fibrous vegetables.

并非所有生酮饮食都是一样的。它们都鼓励追随者限制碳水化合物的摄入，包括面包、糖果、含糖饮料、豆类、水果和土豆。相反，饮食中富含肉类、鸡蛋、奶酪、鱼、坚果、黄油、油脂、种子和纤维蔬菜。

In addition, a recent essay published by several doctors in JAMA Internal Medicinequestioned using the diet as a treatment for obesity and diabetes. They referenced research that suggests the keto diet was no better than low-fat diets in controlling blood sugar for diabetes. The diet could prompt other concerns, including an increase in cholesterol, as well as constipation and fatigue.

此外，《美国医学会内科杂志》上几位医生最近发表的一篇文章质疑了将这种饮食作为肥胖和糖尿病治疗手段的做法。他们引用的研究表明，酮类饮食在控制糖尿病血糖方面并不比低脂饮食好。这种饮食可能引发其他担忧，包括胆固醇升高、便秘和疲劳。

Starting a ketogenic diet

开始生酮饮食

A true ketogenic diet can be hard to maintain, so do it under the care of a doctor or nutritionist to make sure you're getting adequate nutrition. (Photo: Elena Shashkina/Shutterstock)

Following a ketogenic diet can be difficult, because in order to start it, you have to go off carbohydrates almost entirely.

遵循生酮饮食可能是困难的，因为为了开始，你必须几乎完全戒掉碳水化合物。

If you want try a ketogenic diet, do it only under the care of a doctor or nutritionist to make sure you're getting adequate nutrition. The diet cuts out whole grains, legumes and many fruits, and may expose you to too many fats.

如果你想尝试生酮饮食，只有在医生或营养师的照顾下才能确保你得到足够的营养。这种饮食不吃全谷物、豆类和许多水果，可能会让你接触过多的脂肪。

"Instead of engaging in the next popular diet that would last only a few weeks to months (for most people that includes a ketogenic diet), try to embrace change that is sustainable over the long term," writes Marcelo Campos, M.D. for Harvard Health. "A balanced, unprocessed diet, rich in very colorful fruits and vegetables, lean meats, fish, whole grains, nuts, seeds, olive oil, and lots of water seems to have the best evidence for a long, healthier, vibrant life.

哈佛健康医学博士马塞洛·坎波斯写道:“不要去尝试下一种流行的、只持续几周到几个月的饮食(对大多数人来说，包括生酮饮食)，而是要尝试长期可持续的改变。”“均衡、未经加工的饮食，富含丰富多彩的水果和蔬菜、瘦肉、鱼类、全谷物、坚果、种子、橄榄油和大量的水，似乎是长寿、健康和充满活力的生活的最佳证据。”