Key Topic

Many nutritional factors can impact our energy levels, and today we’ll explore the key micronutrients commonly seen in practice, along with some honourable mentions that are also worth considering.

Iron

  • Iron deficiency is obviously the first one that comes to mind because one of the main symptoms is fatigue and low energy.
  • The reduction in haemoglobin reduces oxygen transportation in the body and that leads to feelings of fatigue and lethargy amongst other things. 
  • It is arguably the most common deficiency, with ~30% of the world’s population being deficient.
  • In Australia the stats are a bit better, but it’s still >20% of women who are deficient. And the number gets higher for specific groups e.g. plant based, heavy menstrual bleeding.

B12

  • Fatigue is another common symptom of B12 deficiency.
  • This is for similar reasons where low B12 impacts red blood cell production, reducing oxygen transportation.
  • Because the ability to absorb B12 from food declines with age, deficiency is more common in older adults. 
  • Obviously it’s common in plant based people too if not supplementing it.
  • At a population level, B12 deficiency isn’t that common. But research in Australian aged care facilities has found 14% of people were deficient and another 36% weren’t far off.

Magnesium

  • Magnesium isn’t often linked with energy levels.
  • But there are actually a multitude of ways it can play a role.
  • One example is that it is involved in ATP production, so that could be relevant.
  • But we have also talked about the role of magnesium in sleep.
  • Being magnesium deficient can reduce quality and quantity of sleep and this could have an indirect impact on energy levels. 
  • There is also an association between magnesium supplementation and improved depression scores.
  • A 2023 meta-analysis looking at all the relevant RCTs found significant improvements. This could also translate to subjective energy levels.
  • So between its role in ATP production and correlation with sleep and mental health, it is one to keep in mind when thinking about energy levels.

Vitamin D

  • Low vitamin D is associated with fatigue, but it’s not as clear cut as you’d hope
  • Example: Low vitamin D could just mean low exposure to sun. And low exposure to sun could impact sleep quality. So many more examples like this.
  • In men vitamin D deficiency is linked with low testosterone in men. This could play a role, but similarly, reviews have been a bit inconclusive about whether supplementation helps with that. Or it could also be a proxy for things like sun exposure.
  • Low vitamin D is linked with depression. This could partly be for similar logic, but vitamin D supplementation does have mildly positive evidence for helping here. 
  • Vitamin D deficiency sometimes has fatigue as a symptom identified, but it’s hard to make a strong link.

Honourable Mentions

1. Zinc deficiency can contribute to low energy.

For example, addressing deficiency can increase testosterone production in men, and also improve immunity across the board. Both of which could translate to improved energy levels  

If levels are good though, adding more is unlikely to help.

2. Folate is involved in red blood cell production, so this matters for reasons similar to iron and B12.

3. Iodine is relevant for thyroid function.

A low iodine intake can result in issues with the function of the thyroid and that in turn can lead to feelings of fatigue, although that’s pretty rare in Australia. 

Fun fact, all commercial breads need to be made with iodised salt as iodine deficiency was once a major public health issue 

What to Do With This Information?

If you are feeling low on energy, testing for certain micronutrients can be really helpful. Blood tests are great for checking vitamin D, B12, and iron levels. However, magnesium doesn’t usually show up on standard blood tests. There’s a more accurate test, but it’s not easy to get in Australia. Instead, it’s better to look at your diet and make sure you’re getting enough magnesium. If blood tests aren’t an option, checking your intake of these nutrients can help you spot any potential deficiencies affecting your energy.

Relevant Blogs/Research

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