What Your Blood Test Results Are Actually Telling You

Most of my clients have had blood tests. Many of them have been told their results are "normal" and sent on their way, still feeling awful and none the wiser. This used to frustrate me, and now it drives a lot of how I work.

Because blood chemistry, read well, is an extraordinary window into what's happening inside the body. And "normal" on a standard GP panel is not the same as optimal.

Let me walk you through some of what I look at, and why.

First, let's talk about what blood actually is

Your blood is made up of two main components. The cellular portion, which is about 45% of its volume, contains red blood cells (carrying oxygen and carbon dioxide), white blood cells (your immune defence), and platelets (for clotting). The remaining 55% is plasma, a liquid matrix of water, proteins, electrolytes, hormones, nutrients, and waste products.

When a blood sample is taken and processed, what most labs measure is serum, which is plasma with the clotting proteins removed. Understanding this matters because some nutrients are not reliably measured in serum, magnesium being a perfect example. Magnesium is mostly stored inside cells, so a serum magnesium reading can appear normal even when cellular levels are low. For that reason, I rarely rely on serum magnesium as a meaningful marker.

Getting the most accurate picture: preparation matters

Before I send anyone for a blood test, there are a few things I always go through with them. Being fasted (8 to 10 hours), well-rested, and properly hydrated all affect the results. If someone has just done an intense workout, or is in a period of extreme stress, or has recently been vomiting, their results will not be representative of their baseline.

If you take levothyroxine for your thyroid, take it in the morning and do your bloods in the morning too. For fat-soluble supplements like vitamins A, D, E, and K, I ask for a 10-day washout before testing. For water-soluble ones, three days is generally enough.

One thing that's often overlooked: if haemolysis (red blood cell breakdown) is high in the sample, the results can be completely erroneous. It's worth knowing about because it's a straightforward reason for an inaccurate result.

What I look for in liver chemistry

The liver is the great workhorse of detoxification, hormone clearance, and metabolic processing, so I spend quite a bit of time on liver markers.

ALP (alkaline phosphatase) is one that often gets missed. While it is indeed a liver enzyme, it's also found in the gut lining and in bone. So if ALP is elevated, you need to think about which system it's actually coming from.

Albumin and globulin are proteins made by the liver, and their ratio gives me useful information. When there is systemic inflammation, this ratio tends to drop, which is a quiet but meaningful signal.

If a client has raised bilirubin and particularly if they carry a UGT gene variant, this points to impaired glucuronidation, which is one of the liver's primary phase 2 detox pathways. This pathway is the main workhorse for clearing oestradiol and other hormones from the body. When it's sluggish, hormones recirculate. This is often a key piece of the oestrogen dominance picture that I see in clients with heavy periods, PMS, endometriosis, or hormonally-driven acne.

Homocysteine: the methylation marker most GPs don't check

Homocysteine above 7 is a reliable signal of poor methylation. Methylation is another critical phase 2 liver detox pathway, essential not just for hormone clearance but for DNA repair, neurotransmitter production, and cardiovascular health. If homocysteine is raised, it suggests the methylation cycle is under strain, and that has wide-ranging implications.

This is why I often recommend clients use Randox Health's EveryWoman panel, which measures a broader range of analytes than a standard NHS screen. It's not something I take commission on, I just find it genuinely useful for painting a more complete picture.

Putting it together: your results in context

One of the most important things I've learned is that results only make sense in the context of the individual. What is this person's normal? Has something changed recently, a new medication, a change in life phase like perimenopause or postpartum? Are they pregnant, which naturally dilutes many blood markers?

A result that looks low might simply reflect the fact that someone just ran a half marathon. A result that looks normal might be masking a trend when you compare it to a test done six months earlier.

Blood chemistry is a tool, not a verdict. Used thoughtfully, it can help us understand the metabolic terrain a person is working from and where to focus our support. Used in isolation, without that context, it tells you very little.

If you'd like to work through your blood results with someone who looks beyond the standard reference ranges, I'd love to help. Book a consultation here.