Vitamin B12: Normal Levels By Age

Normal vitamin B12 levels by age are dependent on your intake of this vital nutrient each day. Normal levels of B12 for adults should be more than 250 pg/mL from a B12 biomarker test. Learn the normal levels by age and how much you need to take daily in order to meet your requirements.

Table of Contents:

What Are Normal B12 Levels By Age?

It is important to test for vitamin B12 deficiency in order to determine if you are at risk of abnormal levels of the nutrient. While taking too much is rare, because unneeded amounts are excreted through urine, it is possible to have low levels. If you do not have the normal levels of B12 recommended by age, you may consider vitamin B12 supplements to support optimum intake.


B12 blood tests will measure the biomarkers available in the blood to identify your levels of the vitamin. Although the boundaries may differ depending on the lab, or your need state, these are a indication of what normals B12 levels could be:

  • Insufficient - 100-180 pg/mL or less
  • Potentially insufficient - between 180 pg/mL and 250 pg/mL
  • Sufficient - more than 250 pg/mL

Pg represents a “picogram” which is one-trillionth of a gram.

Older People

The NICE draft guidelines for B12 deficiency highlight age as a risk factor for developing low levels. The body’s ability to produce stomach acid declines with age, meaning the breakdown and subsequent absorption of B12 becomes more difficult. Thus, it may be more likely for older people to suffer from B12 deficiency symptoms.

  • This NIH report shows the normal levels of B12 in older people (60+ years) is between 200 - 900 pg/mL, and that between 300 - 350 pg/mL is ideal.


Children require vitamin B12 as one of their essential nutrients as they grow and develop.

How Much B12 Per Day By Age?

In order to maintain these normal levels of vitamin B12 by age, you’ll need to ensure you get a sufficient dosage of the vitamin every day. How much B12 per day you need will vary depending on factors such as age and lifestyle.


According to the NHS, adults aged 19 to 64 need about 1.5μg (micrograms) of vitamin B12 per day.

Older Adults

As per this 2006 study older adults remedying deficiency or “people aged over 50 with poor vitamin B12 status should intake 500 micrograms of crystalline vitamin B12 per day to help restore low levels”.


The NIH recommends that children need a varying intake of B12 per day as they grow:

  • Birth to 6 months: 0.4µg
  • 7–12 months: 0.5µg
  • 1–3 years: 0.9µg
  • 4–8 years: 1.2µg
  • 9–13 years: 1.8µg
  • 14–18 years: 2.4µg


The sources of vitamin B12 are usually animal products such as meat, fish, eggs, and dairy. Therefore, those following a plant-based diet, or excluding animal products due to allergies, intolerances or lifestyle, may struggle to get B12 as a vegan and reach normal B12 levels.

  • The Vegan Society recommends those following a vegan or plant-based diet take supplements providing at least 10µg (micrograms) of B12 per day to maintain normal B12 levels.

BetterYou’s B12 products are vegan supplements, certified Vegan Approved by The Vegetarian Society, meaning:

  • They contain no animal-derived ingredients
  • Measures are in place to avoid cross-contamination during production
  • They are GMO-free

Testing Your B12 Levels At Home

You can complete a test to determine if you need to increase your intake to achieve normal B12 levels. If you are concerned about your intake, you should consult your Doctor, who may arrange a blood test for you.

There are at-home tests available to determine if you have normal B12 levels by age, without having to leave the house.

You may need multiple tests in order to assess if your supplementation plan is working and your B12 intake has improved to sufficient or normal levels.

Best Vitamin B12 Supplements

The best supplements to help maintain your normal B12 levels by age will be those which are convenient and hassle-free. At BetterYou, our vitamin B12 supplements are formulated to provide the vitamin without having to swallow a tablet.

The best vitamin B12 supplements from BetterYou include:

  • Boost Vitamin B12 Oral Spray - delivers 1,200μg of B12, with a natural apricot flavour.
  • B-Complete Oral Spray - delivers 100μg of B12, with a natural peach, plum and raspberry flavour.

Thanks to our oral spray supplements, you can help to maintain normal B12 levels through fast absorption into the bloodstream. Our sprays bypass the gastrointestinal system, which can cause unreliable B12 absorption.

What Are the Signs of Low B12 Levels?

Low B12 levels, or vitamin B12 deficiency, can cause side effects which can be detrimental to your health. Without sufficient levels, your body cannot complete the vital processes it needs the vitamin for. Some signs of low B12 levels include:

  1. Tiredness and fatigue
  2. Glossitis (sore and red tongue)
  3. Paler skin than usual
  4. Unbalanced mood
  5. Pins and needles
  6. Difficulty concentrating and brain fogginess

If you have normal B12 levels and are experiencing these symptoms, then they may be caused by another issue. If you are experiencing any of these symptoms, or are worried about your B12 levels, you should consult your Doctor.

Who Needs Vitamin B12?

Vitamin B12 deficiency can affect anyone, but there are more “at-risk” groups who may be more susceptible. Those who may be missing out on the benefits of vitamin B12, and may consider supplementation include:

  • Older People - According to the NHS, vitamin B12 deficiency is more common in older people, affecting around 1 in 10 people aged 75 or over and 1 in 20 people aged 65 to 74. This is because the body’s ability to produce stomach acid declines with age, meaning the breakdown and subsequent absorption of B12 becomes more difficult.
  • Vegans - Vegans should consider taking supplements if their diet contains insufficient levels of B12.
  • Those with health conditions - Particularly those which affect the stomach and intestine can impact the ability to absorb normal levels of B12.
  • Those taking medication - If you do take medication, you should check if it affects your normal B12 levels.
  • Pernicious Anaemia - This autoimmune condition impacts your stomach lining, and is one of the primary causes of low B12 levels in the UK.

Supplementing with BetterYou

At BetterYou, we combine nutritional supplementation and our sustainability mission. From our sleep supplements to energy supplements, we use packaging made from plant-based plastic.

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