如今，市面上有多种多样的洗发水可供选择，有许多都声称能改善发质。但洗发水真能做到这一点吗？本期节目讨论洗发产品的原理，以及使用特定类型的洗发水对改善发质是否真的有用。

词汇：toiletries 洗漱用品

Buying shampoo can be overwhelming – there are so many brands to choose from, across a huge range of prices. Some brands promise to repair and nourish our hair, while others promise to strengthen and add volume. But are any of these claims true? Do we even need shampoo at all?

Since long before shampoo was invented – some say in India – our bodies have been producing sebum – an oil-like substance. Sebum stops our skin from getting dry, manages the health of our scalp and makes our hair shiny. But it also collects dirt, and, if left untouched for too long, sebum can cause our hair to become greasy. There are no disadvantages from a health perspective to letting our hair be greasy, says Eleanore Richardson, Trichologist at Fulham Scalp and Hair Clinic, but many people choose to wash their hair regularly for aesthetic reasons.

And so we reach for the shampoo bottle. Shampoos contain a group of chemicals called surfactants. They grab the dirt and grease from the surface of our hair, meaning when we rinse away the shampoo, we also wash away the grease and dirt. But, as Laura Waters, who's a Professor of Pharmaceutical Analysis in the School of Applied Sciences at Huddersfield University, points out, 'some surfactants work too well' and take the natural oils out of the hair, as well. More expensive shampoos may contain less harsh surfactants, but – adds Laura Waters – the type of shampoo doesn't really matter. 'It's on our hair very briefly and gets washed away'. It's the conditioners and styling products that we use after the shampoo that make a bigger difference to the texture and feel of our hair.

Of course, the more we put onto our hair, the more we need to cleanse it off, creating a vicious circle. So, yes, it seems we do have a need for shampoo, but we also shouldn't expect it to be a miracle cure. And, finally, next time you're in a shampoo aisle, remember that hair is made up of dead protein cells and that, sadly, not even the most expensive shampoo can bring them back to life.

词汇表

brand 品牌
repair 修复
nourish 滋养
strengthen 使强韧，强化
volume 数量
sebum 皮脂
oil-like substance 类似油类物质
scalp 头皮
shiny 有光泽的
greasy 油腻的
aesthetic 美观的
chemical 化学品
surfactant 表面活性剂
surface 表层
rinse 冲洗，清洗
harsh 刺激性强的
conditioner 护发素
styling product 美发定型产品
texture （发）质，质地
cleanse 清洁，清洗
miracle cure 灵丹妙药

测验与练习

1.  阅读课文并回答问题。

1. What is sebum?

2. Is it unhealthy if our hair is greasy?

3. True or False? Some surfactants clean the hair too much.

4. What difference can buying a more expensive shampoo make?

5. Which affects our hair more – shampoo, or conditioners and styling products?

2.  选择意思恰当的单词或词组来完成下列句子。

1. This new face cream is supposed to _______ the skin.

grab                                nourish                        rinse                          claim

2. I forgot to wear a hat in the sun yesterday and I got sunburned. Now I have an itchy _______!

brand                              volume                         scalp                          surface

3. There are many _______ treatments to help people change their appearance, including plastic surgery and hair transplants.

repair                              aesthetic                       chemical                    harsh

4. We didn't want to put too many _______ chemicals on our baby's skin, so we switched to organic and herbal soaps and shampoos.

oil-like substance            chemical                       styling products          harsh 

5. The doctor said there is no _______ but that a better diet and more exercise would help.

oil-like substance            styling product               vicious circle              miracle cure    

答案

1. 阅读课文并回答问题。 

1. What is sebum?

Sebum is an oil-like substance that our bodies make to maintain healthy skin and hair.

2. Is it unhealthy if our hair is greasy?

No. Many people choose to wash their hair regularly for aesthetic reasons, but greasy hair is not connected to health.

3. True or False? Some surfactants clean the hair too much.

True. Some surfactants take the natural oils out of the hair, as well as the dirt and grease they're intended to remove.

4. What difference can buying a more expensive shampoo make?

More expensive shampoos may contain less harsh surfactants.

5. Which affects our hair more – shampoo, or conditioners and styling products?

Conditioners and styling products can affect the texture and feel of our hair, but shampoo is on our hair too briefly to really matter.

2.  选择意思恰当的单词或词组来完成下列句子。

1. This new face cream is supposed to nourish the skin.  

2. I forgot to wear a hat in the sun yesterday and I got sunburned. Now I have an itchy scalp!

3. There are many aesthetic treatments to help people change their appearance, including plastic surgery and hair transplants.

4. We didn't want to put too many harsh chemicals on our baby's skin, so we switched to organic and herbal soaps and shampoos.

5. The doctor said there is no miracle cure but that a better diet and more exercise would help.