Anaemia Grades and the Haemoglobin Test

Saw "low haemoglobin" on your test results and got worried? Anaemia grades are divided into mild, moderate and severe depending on how far haemoglobin has fallen, but a single number is not the full answer. For a doctor, the cause matters as much as whether anaemia is present: iron deficiency, low vitamin B12 or folate, hidden bleeding or another disease. In this article we explain how to understand haemoglobin and ferritin tests, what else is checked, which foods are rich in iron and why taking iron on your own is risky.

What is anaemia?

Haemoglobin is an iron-rich protein inside red blood cells. It carries oxygen from the lungs to the whole body. Anaemia is a condition in which there are not enough healthy red blood cells or haemoglobin, so tissues receive less oxygen.

According to the NHS, the most common type is iron deficiency anaemia. WHO lists, alongside iron, deficiencies of vitamin A, folate, vitamin B12 and riboflavin, blood loss, infections and parasitic diseases, chronic disease and inflammation, and inherited blood disorders such as thalassaemia among the causes of anaemia. So "anaemia" is not one disease but a condition with many possible causes.

Anaemia grades: mild, moderate and severe

WHO defines anaemia by the haemoglobin level in the blood. The threshold depends on age, sex, pregnancy, smoking and altitude. For example, according to WHO, anaemia is present when haemoglobin is below 120 g/L in non-pregnant women, and below 110 g/L in pregnant women and children under 5. For men the threshold is different (higher).

Note that some laboratories report in g/L and others in g/dL. 120 g/L = 12 g/dL. Many people compare numbers incorrectly because of this.

The further haemoglobin falls below the threshold, the more severe the anaemia. The exact cut-offs for each grade differ by age, sex and pregnancy, so do not grade yourself from tables on the internet. For a general picture:

Grade	What it means	What may be noticed
Mild	Haemoglobin slightly below the threshold	Possibly no symptoms, or tiredness and breathlessness on exertion
Moderate	Haemoglobin clearly below the threshold	Weakness, dizziness, headache, cold hands and feet, fast heartbeat
Severe	Haemoglobin very low	Signs listed by WHO: pale mucous membranes, skin and nail beds, rapid breathing and heart rate, dizziness on standing, easy bruising

WHO uses the following haemoglobin cut-offs (g/L). Treat them as a general guide: laboratory ranges can differ slightly, and the final assessment is made by a doctor.

Group	No anaemia	Mild	Moderate	Severe
Children 6 months – 5 years	110 or higher	100–109	70–99	below 70
Children 5–11 years	115 or higher	110–114	80–109	below 80
Children 12–14 years	120 or higher	110–119	80–109	below 80
Non-pregnant women (15+)	120 or higher	110–119	80–109	below 80
Pregnant women	110 or higher	100–109	70–99	below 70
Men (15+)	130 or higher	110–129	80–109	below 80

Important: the grade depends not only on the number but on your condition. Doctors consider how quickly the anaemia developed, whether there is heart or lung disease, and how you feel overall. That is why only a doctor should interpret the result.

Haemoglobin and ferritin: what is the difference?

Haemoglobin shows how much "oxygen carrier" is in your blood right now. Ferritin is a protein that stores iron in the body. Its level roughly reflects how much iron is left "in the warehouse".

That is why haemoglobin can sometimes still be normal while ferritin is already low. This may mean iron stores are running down, and it helps catch iron deficiency early in people at risk: women with heavy periods, pregnant women, people who are underweight or absorb nutrients poorly.

Ferritin has a catch, though. According to MedlinePlus (US National Library of Medicine), infection, surgery and other inflammation raise ferritin. So during inflammation a normal or high ferritin does not fully rule out iron deficiency. High ferritin can also be linked to iron overload (haemochromatosis), liver disease, alcohol use or obesity.

What else is checked in a full blood count?

Anaemia is usually found with a full blood count (FBC). According to the NHS, no special preparation is needed, and the test also helps check for other types of anaemia, such as B12 or folate deficiency. A doctor usually looks at:

Haemoglobin and red cell count. Whether anaemia is present and how severe.
Haematocrit. The share of blood made up of red cells.
Red cell indices. Cell size and haemoglobin content; they help suggest the type of anaemia.
Reticulocytes. Young red cells that show how actively the bone marrow is working.
Ferritin and iron tests. Iron stores and iron turnover.
Vitamin B12 and folate. If these are low, taking iron will not solve the problem.

If the cause is unclear, a doctor may order a stool test for hidden blood or refer you to a gastroenterologist or haematologist. Reference values vary by laboratory, age and sex, so do not compare the "normal range" column with another lab's report.

What causes anaemia?

The NHS lists the main causes of iron deficiency anaemia:

heavy and long periods;
pregnancy, often with too little iron in the diet;
bleeding from the stomach or bowel: an ulcer, long-term use of anti-inflammatory painkillers such as ibuprofen or aspirin, bowel inflammation, piles and, less often, stomach or bowel cancer;
any other cause of blood loss.

WHO additionally mentions parasitic infections such as worms, chronic diseases and inherited blood disorders. In everyday life in Uzbekistan there is one more factor: the habit of drinking a lot of tea with or straight after meals. WHO notes that tea, coffee and cocoa slow iron absorption.

Anaemia and tiredness are often linked, but fatigue has other causes too. We cover them in detail in our article on causes of constant tiredness.

Iron-rich foods and vitamin C

Diet matters for preventing anaemia, but diagnosed anaemia cannot always be corrected with food alone, especially when the cause is blood loss. A list based on NHS and WHO advice:

Eat more often	Limit at the same time as iron-rich meals
Lean red meat (beef), poultry, fish	Tea (green and black) and coffee
Pulses: mung beans, chickpeas, beans, lentils	Cocoa
Dark green leafy vegetables	Milk and dairy, calcium supplements
Dried fruit: dried apricots, prunes, raisins	Bran and wholegrain foods high in phytic acid
Nuts, iron-fortified bread and cereals

WHO advises eating iron-rich foods together with sources of vitamin C, that is, fruit and vegetables, because this helps iron absorption. For example, add a tomato and cucumber salad to a mung bean or bean dish, or have a tangerine after the meal. Drink tea a while after eating. Liver is also rich in iron, but the NHS does not recommend it in pregnancy.

If you take calcium and iron supplements, WHO advises taking them at different times of day.

Why is taking iron on your own risky?

"My haemoglobin is low, so I'll take iron" sounds logical, but it carries several risks:

The cause stays hidden. Anaemia can be a sign of an ulcer or hidden bleeding from the bowel. Iron may raise haemoglobin for a while, but the underlying disease remains undiagnosed.
The anaemia may not be due to iron deficiency. With B12 or folate deficiency, thalassaemia or anaemia of chronic disease, iron will not help, and in some cases there is a risk of iron building up.
Side effects. The NHS notes that iron tablets can cause constipation or diarrhoea, stomach pain, heartburn, nausea and darker stools.
Danger for children. According to the NHS, very high doses of iron can be fatal, especially for children. Keep any product containing iron out of children's reach.
Dose and duration. The NHS states that for iron deficiency anaemia tablets are taken as the doctor advises, usually for about 6 months, with repeat blood tests over several months. Only a doctor should manage this.

If you take several supplements, count the iron in all of them and tell your doctor about everything you take.

When to see a doctor

See a doctor if you think you may have anaemia. Do not delay especially if:

weakness, breathlessness and a fast heartbeat have lasted several weeks;
your periods are very heavy or long;
your stools are black and tarry or you see blood in them;
you have unexplained weight loss, abdominal pain or difficulty swallowing;
you are pregnant or planning a pregnancy;
a test showed low haemoglobin, even if you feel well.

With chest pain, severe breathlessness at rest, fainting or heavy bleeding, call an ambulance (103 in Uzbekistan) straight away. For general information see the iron deficiency anaemia page.

How Nutva Immuno can help

Nutva Immuno is a dietary supplement that supports normal immune function. One capsule (500 mg, 60 capsules per pack) contains iron glycinate 68 mg, vitamin C 200 mg, B9 (methylfolate) 400 mcg and B12 (methylcobalamin) 40 mcg. The composition also includes zinc picolinate 125 mg, manganese, copper, iodine, selenium, molybdenum, chromium, vitamin A 2 mg, vitamin E 20 mg, vitamin D3 1000 IU and vitamins B1, B2, B3, B5 and B6.

The product is not a medicine and does not treat anaemia. It does not replace a balanced diet or iron preparations and other treatment prescribed by a doctor. Permit number: №1578927 (Ministry of Health of Uzbekistan), manufacturer NUTVA PHARM LLC.

Precautions. The product contains iron: with diagnosed anaemia the iron dose is set by a doctor, so check with your doctor before taking Nutva Immuno. Also consult a doctor before combining it with other iron or vitamin supplements. During pregnancy and breastfeeding, take it only after agreeing with your doctor. Directions for use: follow the leaflet on the pack and your doctor's advice.

Frequently asked questions

What haemoglobin level counts as anaemia?

According to WHO, anaemia means haemoglobin below 120 g/L in non-pregnant women and below 110 g/L in pregnant women. The thresholds for men, children and teenagers are different. Your doctor will compare your result with the laboratory's range.

Low ferritin but normal haemoglobin: what does it mean?

It may mean iron stores are running down even though anaemia has not developed yet. Find the cause (for example heavy periods or diet) with your doctor and let them decide whether you need iron.

Is mild (grade 1) anaemia dangerous?

Mild anaemia often has no symptoms, but it should not be ignored. Blood loss or another disease may be behind it, and without treatment it can get worse.

What should I eat if I have anaemia?

Lean meat, poultry, fish, mung beans, chickpeas, beans, dark green vegetables and dried fruit. Combine them with fruit and vegetables rich in vitamin C, and save tea and coffee for later after the meal.

Does tea affect anaemia?

Tea, coffee and cocoa slow iron absorption. You do not have to give up tea completely, but it is better to drink it a little after an iron-rich meal rather than with it.

How long should iron tablets be taken?

Your doctor decides. The NHS says that for iron deficiency anaemia tablets are usually taken for about 6 months with repeat blood tests. Do not stop on your own as soon as your haemoglobin is back to normal.