Your Hormones Are Normal. So Why Don’t You Feel Normal?

One of the most frustrating things I hear from patients is:

“My blood tests are normal, but I still don’t feel right.”

Their thyroid hormones might be within range. Their oestrogen or testosterone may look perfectly respectable. Their doctor has looked at the numbers and reassured them that everything is fine.

And yet they’re tired.

Their brain feels foggy. They’re struggling with weight, mood, motivation, temperature regulation, muscle recovery or libido.

So how can the hormone be there, but the effect seem to be missing?

Because having the right amount of a hormone in your bloodstream is only one part of the story.

The hormone has to deliver a message — and the cell has to be able to receive and respond to it.

Think of hormones as messages

Imagine your hormones are sending perfectly good messages.

Thyroid hormone is saying:

“Come on, we need energy. Let’s increase metabolic activity.”

Insulin is saying:

“There’s glucose available. Let’s deal with it.”

Oestrogen is delivering signals involved in everything from bone and brain health to the reproductive system.

Testosterone is signalling into pathways involved in muscle, bone, sexual function and much more.

But sending the message isn't enough.

There has to be someone at the other end able to receive it.

Hormones exert their effects by interacting with receptors and signalling pathways in and around our cells. If that signalling process isn't working optimally, simply having more hormone circulating doesn't necessarily solve the problem.

It’s a little like having full bars on your phone but an app that isn’t responding.

The signal is there. The response is the problem.

This is where the cell membrane becomes interesting

Every one of your cells is surrounded by a membrane.

And it isn't simply a bag holding the contents of the cell together.

The cell membrane is an incredibly dynamic structure made largely from lipids and proteins. It controls what enters and leaves the cell and provides the environment in which many receptors, transporters and signalling proteins operate.

You can think of it as the cell's communications interface.

The physical properties of that membrane matter.

Membranes need an appropriate degree of fluidity — not too rigid and not excessively fluid — because membrane proteins need to move, interact and organise themselves correctly.

The types of fatty acids incorporated into the membrane help influence those properties.

This is one reason why fats are not simply calories.

They literally become part of our cellular architecture.

But aren't thyroid and sex hormone receptors inside the cell?

Yes — and this is an important distinction.

Some hormones, such as insulin, communicate through receptors located in the cell membrane.

Thyroid hormones and steroid hormones such as oestrogen and testosterone primarily exert many of their effects through intracellular receptors — receptors inside the cell that can ultimately influence gene expression.

So it would be an oversimplification to say:

“Bad cell membrane = thyroid hormone can't bind to its receptor.”

The biology is much more interesting than that.

Before a hormone can create its intended effect, several things may need to happen successfully.

The hormone needs to circulate in an available form. It may need to be transported into the cell. It needs to encounter the appropriate receptor. That receptor needs to function appropriately. The hormone-receptor complex may then need to interact with DNA and other regulatory proteins. Finally, the cell has to carry out the instructions.

In other words, hormone action isn't a single switch.

It's a chain of events.

And a blood test is usually measuring one point in that chain.

Thyroid hormones are a great example

You can have a TSH that sits comfortably within the laboratory range.

You can have reasonable free T4 and even free T3.

But those numbers don't tell us everything about what is happening inside individual tissues.

Thyroid hormone action depends on much more than simply how much T4 or T3 is present in a blood sample.

It involves transport into cells, conversion and metabolism of thyroid hormones, thyroid receptor activity, interaction with DNA and the ability of the cell to respond appropriately to that signal.

And different tissues can regulate thyroid hormone signalling differently.

So when someone tells me:

“My thyroid is normal.”

My next thought is often:

Which part of thyroid physiology have we actually measured?

Because a serum hormone concentration and the biological effect of that hormone are not the same thing.

We already accept this concept with insulin

Insulin resistance gives us a useful analogy.

A person can produce plenty of insulin — sometimes considerably more than normal — yet the tissues don't respond appropriately to the signal.

The pancreas compensates by producing more.

For a while, blood glucose may even look reasonably normal because the body is working harder and harder behind the scenes to maintain it.

The problem isn't necessarily a lack of insulin.

It is impaired response to insulin signalling.

That principle — separating the amount of a signal from the biological response to it — is useful when thinking about hormones more broadly.

It does not mean that every person with normal thyroid or sex hormone results has “hormone resistance”.

It means that physiology is more complicated than:

Hormone level normal = hormone function perfect.

What affects cellular signalling?

This is where the wider health picture becomes important.

Cellular signalling and membrane biology can be influenced by nutritional status, fatty-acid composition, metabolic health, inflammation, oxidative stress and other aspects of the cellular environment.

For example, omega-3 fatty acids such as EPA and DHA can become incorporated into cell membranes and influence membrane properties and signalling biology.

Cholesterol also plays an essential structural role in membranes — another reason why describing cholesterol as simply “bad” completely misses its biological importance.

Micronutrients matter too, because hormone signalling ultimately depends on enzymes, transporters, receptors, gene transcription and cellular energy production.

And then there is inflammation.

Chronic inflammatory signalling can alter the way cells respond to other signals. Oxidative stress can affect proteins, lipids and cellular structures. Metabolic dysfunction can change receptor and downstream signalling behaviour.

This is why I am rarely interested in one hormone result in isolation.

I'm interested in the environment that hormone is trying to work in.

Your cell membrane is built from what you give it

One of the things I find fascinating about cell membranes is that they are not static structures.

Their lipid composition can change.

The quality and balance of fats in the diet can influence the fatty acids available for incorporation into membranes.

That doesn't mean that simply taking an omega-3 supplement will suddenly make every hormone work better. Biology is never quite that convenient.

But it does mean that nutrition becomes part of the conversation about hormone health for reasons that go far beyond “eating a healthy diet”.

We're supplying raw materials for the structures through which cells communicate.

That means thinking about adequate essential fatty acids, oily fish and other whole-food sources of healthy fats, sufficient protein and micronutrients, while reducing the metabolic and inflammatory pressures that can interfere with healthy cellular function.

So what does this mean if your hormones are “normal”?

It means that the result is useful — but it isn't the end of the investigation.

If someone has persistent symptoms, I don't think the answer is automatically to push hormone levels higher.

I want to understand the whole pathway.

Is the hormone being produced?

Is it being transported appropriately?

Is it available to tissues?

Can it enter the cells that need it?

Are the relevant receptors and signalling pathways functioning normally?

Is inflammation interfering with signalling?

Is metabolic dysfunction present?

Does the cell have the nutrients and energy required to carry out the message?

And what is the health of the cellular environment more broadly?

Because sometimes the question isn't:

“Do you have enough hormone?”

Sometimes the better question is:

“Can your cells hear the message?”

And that distinction is one of the reasons functional medicine looks beyond whether a result simply falls inside a laboratory reference range.

Your blood test can tell us an enormous amount.

But the number circulating in your bloodstream is only the beginning of the conversation.

A good signal is only useful if the message gets through.

Image by Magnific

‍