Keto. Paleo. Vegan. Vegetarian. Gluten-free, dairy-free, low-carb, carnivore… the list goes on. 

With all of the pop diets out there these days, how do you know which ones are healthy and would suit you?

Through this blog series, we’ll teach you how to evaluate diets based on science – no matter what your favorite influencer says about it. 

We recommend starting at part one, but here’s a recap. When evaluating diets, you’ll want to check on a few different characteristics, including:

  • Fiber intake
  • Polyphenol content
  • Probiotic / fermented food content
  • Electrolyte intake
  • Processed food content
  • Micronutrient intake
  • Caloric intake
  • Fat, protein, and carbohydrate intake
  • Gluten, dairy, or sugar intake: other triggers
  • Price 
  • Sustainability 
  • Adherence / lifestyle match

That sounds like a lot – but tracking these criteria is much simpler than it sounds. 

Let’s jump in! Today, we’ll look at micronutrient (vitamin) intake.

Vitamin Intake

It’s no secret that vitamins are critical to whole-body health. The body uses vitamins as building blocks. Vitamin deficiencies can create a whole host of problems!

Thinking a vitamin deficiency isn’t so bad? Think again!

Vitamin deficiencies can cause:

  • Anemia (decreased blood oxygenation)
    • Due to low iron or vitamin B12 (1, 2)
  • Decreased bone density
    • Due to low vitamin B12, vitamin D, or calcium (3, 4, 5)
  • Chronic fatigue
    • Several different vitamin deficiencies may cause it (6)
  • Hormone fluctuations
    • Several vitamin deficiencies may cause it (7)
  • Irregular menstruation
    • Several vitamin deficiencies may cause it, especially vitamin D (8, 9)
  • Thyroid issues
    • Iodine, selenium, iron, vitamin B12, vitamin D, L-tyrosine, or other vitamin deficiencies may cause them. (10, 11, 12, 13, 14)
  • Hair loss
    • Iodine, selenium, iron, vitamin B12, L-tyrosine, or other vitamin deficiency may cause it. (10, 11, 12, 13, 14)
  • Body composition changes
    • Iodine, selenium, iron, vitamin B12, L-tyrosine, or other vitamin deficiency may cause it. (10, 11, 12, 13, 14)
  • Sleep changes
    • A lack of magnesium, choline, tryptophan or other vitamins may cause it (15, 16, 17)
  • Cognition and memory changes
    • A lack of magnesium, choline, tryptophan or other vitamins may cause it (18, 19, 20)
  • Poor digestion due to low stomach acid
    • A lack of vitamin B12 or other vitamins may cause it (21)
  • Leaky gut syndrome or low gut barrier integrity
    • A lack of Omega 3 fatty acids, zinc, or vitamin D may cause it (22, 23, 24)
  • Poor immune function
    • A lack of Omega 3 fatty acids, zinc, iron, B12, vitamin D, or other vitamins may cause it. (25, 26, 27, 28, 29)
  • Many other problems may ensue!

That’s a long list, huh? Let’s take a look at gut barrier integrity and vitamins in more detail as an example. 

Three vitamins are especially important for gut barrier integrity: omega 3, zinc, and vitamin D (22, 23, 24).

Omega 3 vitamins are valuable for decreasing inflammation in the gut and improving microbiome composition, which can be a root cause of leaky gut syndrome (22). Omega 3 vitamins are also crucial for a healthy hormone balance, indirectly impacting gut health.

1000 mg of Omega 3 vitamins is the daily recommended dose (30)

Zinc is also incredibly valuable for immune and gut health. It is often recommended for those with colitis, Crohn’s disease, dysbiosis, SIBO, parasitic infections, or other gut issues because of its role in repairing gut lining (23).

Lastly, vitamin D is valuable for mending or preventing leaky gut syndrome. A deficiency in vitamin D may cause leaky gut syndrome – so making sure you’ve got enough vitamin D is key to overcoming the syndrome (24).

Vitamin D is a gut health superstar: it decreases inflammation, upregulates beneficial bacteria, improves food breakdown and absorption, and, as we saw above, repairs gut lining.

So let’s take a look at some diets and which vitamins they tend to be deficient in:

Super “clean” diets may be low in iodine. Iodine is found in salt, which these “clean” diets tend to lack. That’s an easy fix – just sprinkle some salt on your food!

Vegan and vegetarian diets tend to be low in iron, vitamin D, choline, and vitamin B12. This issue is an easy fix, too – several supplement companies create affordable multivitamins for vegans.

Carnivore diets tend to be low in several plant-derived vitamins, including folate, vitamin K, manganese, vitamin C, and more. You’ll want to consume a high-quality, broad-spectrum multivitamin if you are a carnivore. Consider adding a greens drink to add at least some polyphenols and fiber.

Keto diets also tend to be low in the vitamins that come from plants. Consider adding in a low-carb greens drink to add at least some polyphenols and fiber. You’ll also want to consume a high-quality, broad-spectrum multivitamin.

When evaluating a diet, check on its vitamin intake to avoid the health threats of vitamin deficiencies.

If you’re curious about the vitamins that your diet of choice provides, record your food for a week in an app that tracks vitamin intake. We recommend Cronometer.

If you’re dead set on sticking with a specific diet, we suggest supplementing with a multivitamin that addresses your needs.

Check out the rest of the blogs in this series to finalize your diet-analysis skills. Tag us on Instagram @igynutrition. Thanks for joining us today! 


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