Health guides

Clear, plain-English answers to common health questions — from blood pressure and cholesterol to weight, blood sugar and heart rate. Every guide links to a free calculator so you can check your own numbers.

29 free guides · educational, not a diagnosis

Weight & body

What is a healthy BMI?

What counts as a healthy BMI — and what your number actually means for you.

How many calories should I eat to lose weight?

The calorie deficit that leads to steady, sustainable weight loss.

How to lose belly fat

Why spot-reduction is a myth, and the habits that genuinely reduce belly fat.

How much protein do I need a day?

Protein targets in grams per kilogram for health, weight loss and building muscle.

What is a good body fat percentage?

Healthy body-fat ranges for men and women, and how it differs from BMI.

How to calculate BMI

The BMI formula in metric and imperial, with a worked example.

What is a healthy waist size?

Healthy waist thresholds for men and women, and how to measure correctly.

How to boost your metabolism

What actually raises your daily calorie burn — and the myths that don’t.

Heart & circulation

What is a normal blood pressure?

The normal blood-pressure range and when a reading is too high.

What does 140/90 blood pressure mean?

What a 140/90 reading really means — and what to do next.

Blood pressure chart by age

Typical blood-pressure ranges by age, and how to read them.

How to measure blood pressure at home

Get an accurate home reading, step by step.

What is a good resting heart rate?

Normal resting heart rate by fitness and age, and how to measure yours.

Signs of high blood pressure

Why high blood pressure is usually silent, and what warning signs to know.

How to lower blood pressure

The lifestyle changes that lower blood pressure, and when medication is needed.

How to lower cholesterol

Foods and habits that lower LDL cholesterol, and when statins are needed.

What are heart rate zones?

Zones 1–5 explained, how to find your max heart rate, and how to train.

What is a good LDL cholesterol level?

LDL reference ranges and why higher-risk people are given lower targets.

Foods that raise cholesterol

Which foods raise LDL — saturated and trans fats — and better swaps.

HDL vs LDL cholesterol: what’s the difference?

Which cholesterol is “good”, which is “bad”, and why the balance matters.

What causes high cholesterol?

The lifestyle, genetic and health causes of high cholesterol — and what you can change.

Cholesterol chart by age

Healthy cholesterol ranges for adults and children, and why targets stay the same with age.

Blood sugar & metabolic

Type 2 diabetes symptoms — am I at risk?

Early signs of type 2 diabetes and when to get checked.

How to lower blood sugar naturally

Everyday food, movement and sleep habits that help lower blood sugar.

What are normal blood sugar levels?

Normal fasting and after-meal blood sugar ranges, plus HbA1c.

Everyday lifestyle

How much water should I drink a day?

How much water you really need for your body, activity and climate.

How many units of alcohol a week is safe?

UK low-risk drinking guidelines, what a unit is, and how to cut down.

Women's health

Early signs of pregnancy

The most common early pregnancy signs and when to take a test.

Children's health

Is my baby a healthy weight?

How growth charts and percentiles show whether your baby is growing well.

Prefer to jump straight to a calculator?

Browse every free checkit.health calculator — instant results, no account needed.

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