What Your Diet Means For Your Hairline

吕思雨

We all know the dangers of a diet thats high in fat. From hypertension to diabetes， heart disease to even some forms of cancer， the range of ailments that can be laid squarely at the feet of eating poorly and being overweight or obese. But a new study from researchers at the Toyko Medical and Dental University （TMDU） in Japan have now found having a fat-heavy diet can also accelerate hair loss.

In the average healthy adult， the hair follicle stem cells（HFSCs） renew themselves regularly which is why your hair grows back when you cut it and also why it becomes longer. As with most things in the human body， though， the onset of age doesnt do the HSFCs any favours and， as you get older， the stem cells lose their ability to replenish as efficiently as they once did， leaving the hair to thin or fall out.

In the study carried out by TMDUs department of stem cell biology， mice that had been given a high-fat diet（HFD） were more susceptible to inflammatory responses in the body which， in turn， blocked follicle regeneration， leading to hair loss. What was surprising was that the deterioration in the hair follicles could happen in as little as four days spent on a high-fat diet and that the problem seemed to be worse in older mice.

“High-fat diet feeding accelerates hair thinning by depleting HFSCs， especially in old mice，”explains Hironobu Morinaga， the studys lead author.“We compared the gene expression in HFSCs between HFD-fed mice and standard diet-fed mice and traced the fate of those HFSCs after their activation.

Its not just the fat content of your food that can play havoc with your hair as what you consume can really affect how your hair grows and even whether men will keep it， as consultant dermatologist DrAliaAhmed explains.

Nutritional deficiencies are often the root cause of many hair problems， adds Dr Ahmed.“Iron， zinc， niacin， folic acid， biotin， vitamin A， vitamin D， vitamin E—there are so many nutrients implicated in hair disorders，”she says.“Its not just genetics.”

If youve got a sweet tooth， for example， you may need to think about putting down those Percy Pigs. Not only is sugar bad for your hair， but it can cause your blood sugar levels to spike which， in men， can raise the levels of the hormone androgen， leading to follicle damage and potential hair loss.

But dont make the mistake of swapping sugar for artificial sweeteners. Take diet fizzy drinks that replace processed sugar with artificial sweeteners like Aspartame， for instance. In their analysis of aspartame， the United States Food and Drug Administration （FDA） has listed hair thinning and hair loss as one of the main side effects of excessive aspartame consumption.

Drinking alcohol might not lead to hair loss in men（largely because it acts to suppress testosterone） but the condition of your locks will certainly be affected by one too many as it reduces your bodys ability to absorb key nutrients like folic acid and zinc， making your hair prone to damage like split ends and brittleness. Go easy on salt too. Its been shown to cause hair shedding as well.

我们都知道高脂肪饮食的危害。高血压、糖尿病、心脏病，甚至一些癌症都可以直接归咎于饮食不健康或肥胖。但日本东京医科齿科大学（TM？ DU）研究人员的一项新研究发现，高脂肪饮食也会加速脱发。

一般健康成年人的毛囊干细胞会定期自我更新，这就是为什么你剪掉的头发会长回来，也是头发会变长的原因。然而，与人体内的大多数情况一样，年龄对毛囊干细胞没有任何好处，随着年龄的增长，干细胞失去了以前那样的更新能力，导致头发变少或脱发。

在东京医科齿科大学干细胞生物学系开展的研究中，高脂饮食喂养的小鼠更容易受到体内炎症反应的影响，而炎症反应会阻碍毛囊再生，导致掉毛。令人惊讶的是，短短四天的高脂肪飲食就可让毛囊发生退化，而老年鼠的问题似乎更严重。

该研究的主要作者Hironobu Morinaga解释说：“高脂肪饮食喂养让毛囊干细胞变少，特别是老年小鼠。我们比较了高脂肪饮食喂养的小鼠和标准饮食喂养的小鼠之间毛囊干细胞的基因表达，并追踪了这些毛囊干细胞激活后的命运。

皮肤科顾问医生艾莉亚·艾哈迈德博士解释称，不仅仅是食物中的脂肪含量会破坏你的头发，吃的东西会影响头发的生长，甚至影响男人能否保住头发。

艾哈迈德博士补充说，营养缺乏往往是许多头发问题的根本原因。“铁、锌、烟酸、叶酸、生物素、维生素A、维生素D、维生素E——头发疾病涉及到太多营养素。不仅仅是遗传因素。”

例如，如果你喜欢吃甜食，你可能需要考虑放弃那些橡皮糖。糖不仅对你的头发有害，而且会导致血糖水平升高，而男性的血糖升高会导致雄激素水平升高，导致毛囊损伤和潜在的脱发。

但用人工甜味剂代替糖是错误的，不要这么做。以阿斯巴甜等人工甜味剂代替加工糖的低糖汽水为例，美国食品和药物管理局（FDA）在对阿斯巴甜的分析中发现，头发稀疏和脱发是阿斯巴甜摄入过量的主要副作用之一。

饮酒可能不会导致男性脱发（主要是因为酒精能抑制睾丸激素），但头发肯定会受到很大影响，因为饮酒会降低人体吸收叶酸和锌等关键营养素的能力，使头发容易出现分叉和脆弱等损伤。盐也要少吃。有研究表明，盐也会导致脱发。