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There are several instructions to heed when administering a lab test. One of the processes is fasting before the collection of samples. Some diagnostic tests deal with fasting; you can not do such a test without fasting. Therefore it is required that you remain hungry than regret the result of not heeding the advice later.

Hence, you might ask yourself why fasting is essential before undergoing some test? And which of the lab test needs fasting? Read on to get the answers to your questions.

The Importance Of Fasting Before Test

Any food you consume causes a visible change in your blood composition. When all the organs of your body are working correctly, the variation settles down after some time has passed. Hence, fasting for at least 10-12 hours is vital for us to assimilate the actual functioning of our body parts. Fasting ensures no external influence in the composition and gives the exact way our organs perform.

If the result came out to be expected, you would know that you have a healthy body. But when the effects are adverse, it calls for precautions and treatment.

We are going to list out the few tests that fasting is paramount. These are:

Vitamin B12:

Vitamin B12 is a vital vitamin in our body that helps break down metabolic activities in our body. It does a lot more like; helping to maintain the blood cell production, nerve health and brain. The test is conducted to know the vitamin B12 I present in the body.

Doctor asks for the test when you exhibit the below symptoms:

  • Weakness
  • Loss of appetite
  • The confused state of mind
  • Little trouble in breathing
  • Hands and feet exhibit a tingling sensation.

Fasting Hours and Preparation:

Hydrating your body before the commencement of the test is essential. Therefore, fasting for 8-10 hours is vital before beginning the test. So before the duration reaches you have to drink enough water.

Normal level:

Every day, all adults need to have a 200 – 900pg /ml level. But, numerous factors are what determine the B12 levels in the body. Hence, following the doctor’s advice is essential because it will help you know your results exactly.

C peptide:

The pancreas enables insulin to generate in the body, which the byproducts formed are regarded as C peptides. The substance we consume is usually broken down into glucose and essential nutrients. While the work of insulin is to produce absorbs the glucose and helps regulate the level of sugar in the body.

Insulin C peptides test will be conducted. C peptides that are lesser show that the generation of insulin is less generation of insulin and a higher level of sugar. The test helps to know if it is a type 1 or type 2 diabetes inpatient.

The following symptoms are what will make doctors prescribe the test.

  • Frequent urination
  • Blurred vision
  • Excessive hunger
  • Fainting and dizziness
  • Heart palpitations
  • Quick irritations
  • Frequently confused

Fasting Hours and Preparation:

The patient’s age determines the preparation, and medical practitioners will give the best suggestions. It requires 12 hours of fasting.

Normal levels:

C peptides levels are usually between 0.5 –2 nomograms per millilitre under normal conditions. But, it is also crucial to visit a doctor for the complete results.


Other blood tests require fasting or different kinds of preparation. Try out the NHC brand of liposomal vitamin C that helps in boosting the immune system and provides a high level of available antioxidant that is rich in vitamin C formula. It is also suitable for collagen formation and stress-free.

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