Should I fast before taking my test?

When should I take the blood sample?

When should I do my test after my COVID vaccine?

How often should I take a test?

How do I collect my sample?

Before sample collection

During sample collection

Still struggling to collect your sample?


Should I fast before taking my test?

Hint: yes.

We recommend that you fast (don't eat) for 8 hours before collecting your blood sample. This will allow our labs to attain the clearest results to measure your health.

The easiest time to do so is first thing in the morning before breakfast – and having had a shower helps get the flow going too!

Make sure to drink lots of water — because being hydrated is one of the best things you can do to prepare.

Psst! Drinking black coffee and tea beforehand is absolutely fine ☕️


When should I take the blood sample?

Hint: we recommend first thing in the morning.

We recommend taking your sample first thing in the morning during the week. And posting your sample as soon as possible after it's collected. If you take the test during the day, it's best to post the sample before the last postbox collection of the day.

The lab is open to receiving delivery of samples on Saturday and Sunday — but confirmation of receipt emails are only sent out from Monday to Friday. 

Please note if you're taking a testosterone test — it's important to collect the sample first thing in the morning around 9am, before eating.


When should I do my test after my COVID vaccine?

Short answer: after two weeks.

The following test results may be impacted by a recent COVID-19 vaccination:

  • Coronavirus antibody test

  • hs-CRP test

  • and Ferritin.

The results for hs-CRP (high sensitivity C-Reactive Protein) may be raised in response to the COVID-19 vaccine. This means you may see higher hs-CRP levels if you have recently received the vaccine.

Ferritin is a marker of iron stores and is also found in our Advanced Iron Profile test. It's also an ‘acute-phase reactant’. This means it's a marker that increases rapidly when you currently or recently had an infection or virus — or when there is a level of inflammation within the body.

Vaccines help develop immunity by imitating an infection and triggering an immune response. So CRP and Ferritin levels can increase because of infection or inflammation caused by this response.


We recommend waiting two weeks to do these tests after having the vaccine.


How often should I take a test?

Hint: it's up to you!

We believe it's most effective to monitor your internal health regularly over time. So we recommend taking your test every three months. This is the amount of time it takes to see the impact of health and lifestyle changes.

It's completely up to you though. Some people might want to test monthly, whilst others would prefer every six months — you can change the frequency of your subscription from your Thriva dashboard at any time.


How do I collect my sample?

Here's how!

Collecting your sample might be a bit daunting. But don’t worry, follow our video guide and you’ll get the hang of it:


Before sample collection

We recommend giving yourself 30 minutes to do your test, especially if it’s your first time.

  1. Drink enough water the day before your test — you’ll struggle to get enough blood if you’re dehydrated.

  2. Fast for eight hours before collecting your sample — doing it in the morning before breakfast is usually the easiest.

  3. Drink 1-2 big glasses of water at least 30 minutes before doing your test.

  4. Soak your entire hand (not just the tips) in warm water for 2 minutes.

  5. Skip on the spot (if you can) to get your heart rate up — this helps your blood to flow quicker.

Prick the corner of your fingertip — it’s less sensitive and makes it easier to direct your blood. And make sure your finger is on a hard surface so the lancet can work properly.


During sample collection

  1. Stand up for the whole process — gravity helps your blood flow to your finger.

  2. Massage your hand in a firm downward motion — beginning below your wrist to just before the prick on your finger. Don’t squeeze too hard as it can damage your blood cells and we won’t be able to test it.

  3. Wait 3-4 seconds between each massage — you need a little time for your blood to refill.

  4. If the blood stops flowing:
    Wipe the piercing with clean tissue — this helps remove any clots that can stop your blood flow. If this doesn't work, re-prick a different finger using a new lancet. You can warm your hand again before re-pricking if needed.

  5. Fill the yellow tube to at least the second line:
    Put the cap on and turn upside down about 10 times so your blood touches the gel at the bottom. If you have a purple tube, fill this before capping your yellow tube.

  6. Fill the purple tube to at least the first line (not all kits have a purple tube):
    Immediately put on the cap and swirl so your blood touches the gel on the sides of the tube.


    What do I do if I'm still struggling to collect my sample?

    If you run out of lancets or need a replacement kit — follow this link here.


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