Energy Test

Iron, Vitamin D & Thyroid function

Check the most common reasons for lack of energy

Feeling tired all the time is one of the most common symptoms that people report. This test looks at the most common reasons that cause this feeling of lethargy: Thyroid function, Vitamin D levels and Iron levels. What's included?


Order now

Your personal report

Every customer receives a bespoke report written by one of the GPs on the Thriva platform. We'll explain in plain english what your results mean and what action you need to take next.

What's tested?

Tdl logo grey

All of our tests are performed by our accredited partner labs. View details

Vitamin D

The main source of vitamin D is sunlight, but in the UK we can't make any vitamin D from winter daylight between November and March and so Vitamin D deficiency is common in men and women of all ages. For others, the kidneys have trouble converting the nutrient to its active form or their being overweight makes vitamin D less available for use in the body.

  • 25-hydroxy Vitamin D
    Vitamin D helps your body absorb calcium. Vitamin d deficiency is linked to fatigue, bone and muscle pain, as well as getting ill more often than usual

Thyroid Function

The thyroid is a gland found in the neck. It produces hormones that are released into the bloodstream to control the body's growth and metabolism. An overactive or underactive thyroid leads to hormone imbalances which can cause symptoms such as tiredness, weight gain and feeling depressed.

  • Thyroid Stimulating Hormone (TSH)
    Thyroid-stimulating hormone is a pituitary hormone that stimulates the thyroid gland to produce thyroxine, and then triiodothyronine which stimulates the metabolism of almost every tissue in the body.
  • Free Thyroxine (FT4)
    Thyroid hormones not bound to proteins. FT4 lowers when the thyroid is struggling.

Iron Levels

Iron is used to produce red blood cells, which help store and carry oxygen in the blood. If you have fewer red blood cells than is normal, your organs and tissues won't get as much oxygen as they usually would. This can lead to what is know as Iron deficiency anaemia which can cause fatigue, shortness of breath, dizziness, headache, coldness in your hands and feet, pale skin, and chest pain. Treatment for iron deficiency anaemia usually involves taking iron supplements and changing your diet to increase your iron levels.

  • T.I.B.C.
    Total iron binding capacity (TIBC) tests to see if you have too much or too little iron in the blood. Iron moves through the blood attached to a protein called transferrin.
  • Unsaturated iron binding capacity (UIBC)
  • Iron
    Iron is an important part of hemoglobin, which carries oxygen from your lungs to the rest of your body. Low iron levels can cause fatigue, shortness of breath, anxiety and head pain
  • Ferritin
    Ferritin isn’t the same thing as iron in your body. Instead, ferritin is a protein that stores iron, releasing it when your body needs it. Ferritin usually lives in your body’s cells, with very little actually circulating in your blood.
  • Transferrin Saturation
    Transferrin is a blood protein that picks up iron absorbed by the intestines and transports it from one location to another. When iron absorption is abnormally high, transferrin proteins become more saturated with iron. An elevated TS value therefore reflects an increase in iron absorption.
Packaging contents

What's in the kit?

Your thriva health kit will include everything you need to take your simple finger-prick blood test including detailed and easy-to-follow instructions. Each kit includes lancets to prick your finger (no needles!), a small collection tube and a prepaid envelope to return your sample.

More details

Ready to get started?

Order now

What our customers say

4 19 6 22 9 15 17 13 7 26 25 16 10 3 21 24 1 12 23 5 20 28 2 14 18 11 27 8