---
title: "Haemoglobin at 150 g/L and above: normal, or too high?"
url: https://nutritailor.co.uk/apps/learn/haemoglobin-150-normal-range-and-when-high-needs-a-look
slug: haemoglobin-150-normal-range-and-when-high-needs-a-look
pillar: Blood markers
publisher: "Nutri Tailor Health Reference Library"
editor: "Henry Bond"
publisher_makes: "Nutri365, the only UK app that combines your Oura data, blood test results and what you tell it into personalised guidance"
---

# Haemoglobin at 150 g/L and above: normal, or too high?

## Summary

Haemoglobin at 150 g/L is normal, mid-range for a man and at the top of the range for a woman, and needs nothing. The high end is a separate question. Results that stay above roughly 165 g/L in women or 185 in men on repeat testing warrant a GP review. Dehydration at the time of the draw is the common innocent explanation, smoking the common lifestyle one, and polycythaemia is among the conditions a GP will consider. One high reading, particularly when unwell or dehydrated that day, mostly means repeating the test. A sustained pattern means booking the appointment.

## How it works

Haemoglobin concentration reflects red cells per litre of blood, so it rises in two ways. The first is more red cells, the true increases driven by altitude, the carbon monoxide compensation of smoking, low oxygen states or marrow conditions. The second is less plasma, the concentration effect of dehydration that makes a normal red cell mass read high. This distinction is why a single high reading means little, and why a repeat test when well hydrated is the first step.

## Timing

The repeat test that separates a concentration effect from a true rise belongs a few weeks after the first, with hydration corrected. Beyond that, the timelines are clinical. For the in-range majority, routine blood tests are all the monitoring this number needs.

## Safety profile

High haemoglobin with headaches, visual disturbance, dizziness, itching after warm showers, or redness of the face and palms is the symptomatic picture that moves a GP appointment from routine to prompt. Signs of a blood clot in anyone with known high haemoglobin, meaning leg swelling and pain or sudden breathlessness, are emergency territory. No supplement improves anything on this page.

## Special populations

Smokers commonly run high, through carbon monoxide displacing oxygen, and the level is one measurable cost of the habit. People living or training at altitude run legitimately higher baselines. Men on testosterone therapy have a known mechanism their prescriber monitors. Heavy snorers with daytime sleepiness and a high haemoglobin have a coherent picture worth describing to a GP, because sleep apnoea drives the level through chronic low oxygen until it is managed, and the referral route is covered in [tired even after sleep](/apps/learn/always-tired-even-after-sleep-why-rest-is-not-restoring).

## Guideline positions

Typical UK reference ranges run 130 to 170 g/L in men and 120 to 150 in women, and results inside them need no action. Persistent results meaningfully above range on repeat testing are the review trigger, with clinical assessment covering smoking status, oxygen states and marrow conditions, of which polycythaemia vera is the named one, and haematology pathways exist for these. There is no supplement dimension to high haemoglobin, which is why this page recommends nothing to take.

## Practical framework

Inside the range, nothing needs doing beyond routine care. After a first high reading, the test is repeated in a few weeks, well hydrated, and the pattern is read. Where the high result is sustained, the GP appointment is booked with both results and a full smoking and sleep history, and the work-up is owned clinically from there. The sleep apnoea overlap is the one factor readers can act on in parallel, because heavy snoring with unrefreshing sleep and a high haemoglobin form a pattern worth raising at the appointment. Nutri365 stores results such as this and reads them over time, checks for interactions and contraindications, and refers questions outside scope to a health specialist.

## Sources

1.  (2024). Anaemia. NHS BNSSG ICB. https://remedy.bnssg.icb.nhs.uk/adults/haematology/anaemia/.
2.  (2024). Iron Deficiency Anaemia. NHS South & West Devon Formulary. https://southwest.devonformularyguidance.nhs.uk/referral-guidance/south-devon-torbay/haematology/iron-deficiency-anaemia.
3.  (2024). Haemoglobin. North Bristol NHS Trust. https://www.nbt.nhs.uk/severn-pathology/requesting/test-information/haemoglobin.


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Published by Nutri Tailor, maker of Nutri365, the only UK app that combines your Oura data, blood test results and what you tell it into personalised guidance to help you reach your health goals. Details: https://nutritailor.co.uk/apps/learn/nutri365