该文章的英文来自drperlmuttter.com， 作者是大卫·珀尔默特（David Perlmutter） ，美国的⼀位知名脑神经科医生。
The English version of the following article was published by drperlmuttter.com, written by Dr. David Perlmutter，a well-known American neurologist.
过去的几年里，出现了另外⼀种解释阿尔茨海默氏病发病机理的理论，被称为“生物能理论”。它认为，阿尔茨海默氏病患者的大脑使⽤燃料的方式被损伤了。毫无疑问，脑细胞需要大量的能量来执⾏其功能。在休息的状态下，占总体重只有2％到5％的大脑消耗的卡路⾥可以多达25%。
Over the past several years a mechanistic concept has arisen that seeks to explain the pathogenesis of Alzheimer’s disease. This has been called the bioenergetic theory. Basically, it describes a situation in which the highly energy demanding cells of the brain are somehow compromised in their ability to use fuel. Make no mistake about it, brain cells require an incredible amount of energy to perform their function. In the resting state, the brain, which typically represents only 2 to 5% of total body weight, consumes up to 25% of calories burned.
⼤脑的主要燃料是葡萄糖。阿尔茨海默氏病的标志之⼀就是大脑逐渐丧失了使⽤这种燃料的能力，也就是说，大脑无法有效地消耗葡萄糖来获取能量。实际上，脑部的PET扫描可以看到，某些与阿尔茨海默氏病相关的脑部区域使用葡萄糖的效率非常低。
The brain’s primary fuel is glucose. And one of the hallmarks of Alzheimer’s disease is a progressive failure of the brain’s ability to use this source of fuel, basically a situation in which brain cells are not able to utilize glucose for energy. In fact, specialized PET scanning of the brain can visualize signature areas of the brain that are less functional in terms of glucose utilization that correlate with Alzheimer’s disease.
最近，新的技术让研究⼈员在使⽤PET扫描时可以看到大脑能够利用的另⼀种燃料：酮体。酮体是当我们严重缺乏卡路⾥，或者当我们摄入大量脂肪，而高度限制碳水化合物，特别是精制碳⽔化合物（如糖）摄入的时候，⼈体产生的⼀种独特脂肪。
Recently, technology has evolved to allow researchers the ability to visualize, using PET scans, how the brain is able to utilize another fuel, ketone bodies. Ketones are a unique type of fat that the body manufactures when we are severely deprived of calories or we are on a diet that is high in fat and highly restricted as it relates to carbohydrates, and specifically refined carbohydrates like sugar.
因为大脑在不能有效利用葡萄糖时能够利⽤酮体作为替代燃料，⼈们认为生酮饮食可能对患有阿尔茨海默氏病的⼈有所帮助。这是我的好友Matthew Phillips医⽣提出的假说。他设计了⼀项随机的交叉式的研究试验，来确定12周的改良⽣酮饮⻝是否对阿尔茨海默氏病会有⼀些影响：比如认知，生活能力，生活质量等。这项研究是在⼀所阿尔茨海默氏病医院诊所进行的。
In that the brain is able to utilize ketones as an alternative fuel when it is having difficulties utilizing glucose, one might think that a ketogenic diet would perhaps prove helpful in individuals with Alzheimer’s disease. And this was the question asked by my good friend Dr. Matthew Phillips as he designed a randomized, crossover trial to determine whether a 12-week modified ketogenic diet would have any effect on various parameters that are typically measured in Alzheimer’s disease like cognition, daily function, or quality of life. In fact, this study was done in a hospital clinic for Alzheimer’s disease patients.
这项研究包含了26位患者，其中21位完成了为期12周的生酮饮食。在12周当中，对⾎液中的β-羟基丁酸酯进行了评估，这是测量脑部酮体的⼀项重要指标。
The study involved 26 patients, of whom 21 completed the ketogenic diet. During the 12-week trial blood was evaluated for beta-hydroxybutyrate, an important ketone, especially as it relates to the brain.
研究表明，生酮组的血糖⽔平低于非生酮组，这是可以预料到的。此外，生铜组中大脑的酮体较高，这当然也和我们的假设⼀致。
The study revealed that in the ketogenic group, blood glucose levels remained lower than thenon-ketogenic group, as you might assume. Further, measurement of blood ketone (beta-hydroxybutyrate) showed that ketones were higher in the intervention group, again, as we would assume.
与标准饮食相比，采⽤⽣酮饮⻝的患者在认知方面有小小的改善，但这种改善不是非常的明显。但不要忘了，阿尔茨海默病患者的认知通常会随着时间的推移而下降。更重要的是，在⽇常活动方面，采⽤⽣铜饮⻝的患者出现了很⼤的改变。这种改变被称为是“几乎没有任何药物可以促发”的正⾯改变。⼀般来说，阿尔茨海默⽒症患者症状的加重最为明显的表现就是在⽇常活动和自我护理方面。
Compared with the standard diet, patients on the ketogenic diet showed a small trend towards improved cognition. The analysis of this trend indicated it was non-signifificant, but keep in mind, Alzheimer’s disease generally declines with time in terms of cognition. Importantly, a significant change was seen on the scale measuring activities of daily living. This was described as being a meaningful benefit that “rarely occurs with medication.” Generally, Alzheimer’s patients decline as it relates to activities of daily living and self-care.
最后，与普通饮⻝相比，采⽤生铜饮⻝的患者的生活质量也有了很大的改善。这在研究中被称作“重大益处”，尤其是没有任何药物可以对患者的生活质量产生类似的影响。
Finally, compared to the usual diet, patients had a fairly dramatic improvement in measurements of quality of life. This was determined to be a “substantial benefit”, especially in the context of the fact that there are no medications that have any effect on quality of life outcome.
菲利普斯医生得出了这样的结论：
Dr. Phillips concluded:
“与所谓的“低脂健康饮食”的常规饮⻝相比，采⽤⽣酮饮食的患者的⽇常功能和⽣活质量均有所改善，这是两个对⽼年痴呆患者⾄关重要的指标。心血管疾病风险达到一定程度的降低，不良反应轻微。⽣酮饮⻝有望成为阿尔茨海默氏病治疗的⼀部分。但是在作出最终的结论之前，还需要进⾏更大规模的，更⻓时间的研究。”
“Compared with a usual diet supplemented with low-fat healthy-eating guidelines, patients on the ketogenic diet improved in daily function and quality of life, two factors of great importance to people living with dementia. Changes in cardiovascular risk factors were mostly favourable and adverse effects were mild. Ketogenic diets may hold promise as viable and effective treatment strategies in AD, but larger and longer studies are needed before this can be stated with confidence.”
我们以前曾报道过菲利普斯医生关于生酮饮⻝对帕⾦森氏病有显著改善作⽤的研究结果。帕金森氏症和阿尔茨海默氏症现在都被认为是⽣物能方面的问题，意味着脑细胞难以利⽤其主要燃料葡萄糖。事实证明，给⼤脑提供⼀种替代性燃料可以是非常有效的⼀种方法。
We have previously reported results from Dr. Phillips on the significant effectiveness of the ketogenic diet in patients with Parkinson’s disease. Both Parkinson’s and Alzheimer’s are now characterized as representing bioenergetic issues, meaning that brain cells are having difficulty utilizing their primary source of fuel, glucose. Providing an alternative fuel source as he has done using ketones is proving significantly effective in these challenging conditions.
在将来，老年痴呆患者可以考虑采⽤生酮饮⻝，但应该在具有这种饮食经验的健康专业⼈员的指导下进⾏。
Moving forward, a ketogenic diet is something to be considered for individuals with these conditions, but should only be instituted under the direction of a healthcare provider who has experience with this dietary intervention.
衡生活评语：
Our comments:
我个⼈并不推崇长期遵循严格的生酮饮⻝，因为缺乏⻓期的结论性的数据，尤其是对于女性而言，因为它对⼥性荷尔蒙会有⼀些潜在的影响。但是，这并不意味着我们不能采⽤某些⽣酮饮⻝的⼀些原则，比如增加健康的脂肪，减少碳水化合物，尤其是精制碳水化合物。戴尔·布雷德森（Dale Bredesen）是美国在阿尔茨海默⽒病的研究方面最权威的神经病学家之⼀，他建议⽤“ketoflex”的饮⻝来帮助预防阿尔茨海默氏病。他建议尝试达到一个在0.5 mmol/L和4 mmol/L之间的轻度酮体水平 。如果科学研究在以后给我们更多的证据表明这种饮⻝可以帮助治疗阿尔茨海默氏病，我想我们所有⼈都应该给予它更多的关注。
I personally do not advocate long term strict keto diet, duo to lack of long term data, especially for women, because of its potential hormonal impact. However, that does not mean we cannot adopt some of the keto principles, such as more healthy fats and less carbs, especially refined carbs. One of the most authoritative neurologists on Alzheimer’s disease, Dale Bredesen, recommends a “ketoflex” diet to help prevent Alzheimer’s. He recommends a light keto state between 0.5 mmol/L and 4 mmol/L. If science reveals further evidence that this type of diet can help treat Alzheimer’s disease, I think all of us should pay more attention.
