The Magic Supplement

Dry skin. Oily eyelids. Water retention. Fatigue. Weight gain.

At first glance, they don't sound like they belong together. Yet, for one patient, they all had the same underlying cause.

Lottie, 27, worked in a famous, high-end London department store. On the shop floor all day, her priority was always the customers — sadly, at a cost to her health.

As we unpacked her intake form, she joked that she drank a teaspoon of water every day. That was my first clue.

Many people don't realise that the brain often struggles to distinguish hunger from thirst. It's one of the reasons I always ask patients to have a glass of water when they "feel" hungry in between meals.

But appetite aside, water plays an important role in skin. When we don't drink enough, it gets dry. So far so good. What's counterintuitive is the water retention bit.

Let's imagine a scenario where money is scarce. You wouldn't exactly spend it freely. In fact, penny-pinching is likely to become the norm over time. That's exactly what happens with a water shortage in the body. We retain it.

Another symptom explained.

But what about the oily eyelids? Well, when the cells retain water, they don't do it in a way that actually nourishes the skin, because the skin, in general, is not considered a vital organ.

But the skin we are talking about is on the eyelids. Why would they be oily then? Because the brain is a vital organ. If the dry skin on your arm caused your entire arm to fall off, you would still function. If your brain fell out, not so much.

And so, Mother Nature has a little hack to make sure that doesn't happen: sebaceous glands. They look a little like the bulbous end of a pipette and when there is danger (like too much dry skin in a vital area), they squirt out oil: hello oily eyelids.

Of course, there are other factors in play with skin (which I will talk about in the coming weeks), but you start to get a picture of why water is so important.

Lastly, fatigue. Water is involved in almost every metabolic process in the body. Even mild dehydration can leave you feeling foggy and sluggish. So while a human can go several months without adequate food intake, the evidence shows that when water intake is taken to zero, the average human can survive a week, at best. Water really is essential.

And so, as the stress hormones begin to kick in, cortisol will slow down the metabolism and we start to gain weight — even on the same diet.

Six weeks in, Lottie's skin — both on her face and body — is glowing, the water retention is a thing of the past, her energy has returned and she has already lost 2kg.

Not bad going by adding a "supplement" that is pretty much free.

So the next time you think you need another lotion or pill, go back to basics.

Sometimes the answer is as simple as a glass of water.