Lauren Manaker, MS, RDN, LD, CLEC - registered dietitian | Feb. 2021

Everytime Monday rolls around, plenty of people start a new diet. And while some diets involve limiting portion sizes or refraining from enjoying food over certain hours of the day, others require limiting entire food groups. While cutting certain foods from your diet can result in weight loss, it can also put you at risk for nutrient deficiencies.

In fact, according to one study, people who followed certain restrictive diets – think Atkins and The South Beach Diet – had six micronutrient deficiencies (vitamin B7, vitamin D, vitamin E, chromium, iodine and molybdenum). Yes, the numbers on the scale may trend down when you are following a restrictive diet, but your vitamin and mineral levels can dip as well if you aren’t careful.

Three diets that are extremely popular and require restricting certain foods include the vegan diet, Whole30 and the ketogenic (keto) diet. Read on to learn which nutrients you may be missing if you are following one of these diets any time soon.

Vegan Diet

Following a vegan diet involves avoiding anything that comes from an animal. So, foods like meat, fish, milk and even honey are off the table. If you follow this diet, expect to eat a diet rich in fruits, vegetables, beans, legumes, nuts and grains.

It is true that following a vegan diet may result in weight loss, a reduced risk of heart disease and help alleviate arthritis pain. But this restrictive diet can also leave you with some nutrition gaps.

Animal products are typically rich in key nutrients like vitamin B12. Therefore, every person who follows a vegan diet should ensure that this important nutrient is supplemented appropriately to prevent a deficiency. Lucky for you, MegaFood makes a Vegan B12 tablet, as well as two amazingly delicious B12 Energy gummies (cranberry and ginger) that are vegan too!

Consuming vegan foods might also make it challenging to get enough iron in your diet. Blood Builder® to the rescue! This best-selling supplement was shown in a clinical study to increase iron levels without side effects.†*

Other nutrients like calcium, zinc & vitamin D may be challenging to consume in adequate amounts when living a vegan lifestyle – nothing that can’t be fixed with proper supplementation. Shop MegaFood vegan supplements.

Whole 30

When following this diet, you avoid all soy, dairy, grains, alcohol, legumes and added sugars from their diet for 30 days straight.

Many grains are fortified with B vitamins, including folic acid, thiamin, niacin and riboflavin. Avoiding grains without ensuring proper intake of these nutrients can result in an inadequate intake of these nutrients. And saying goodbye to soy and dairy foods can put a person at risk for inadequate bone-building calcium and magnesium intake, depending on what the rest of the diet is looking like.

Generally speaking, following the Whole30 diet can mean a lack of calcium, certain B vitamins, magnesium, vitamin D and more. These nutrients are essential to bone health, immune health and more, so making sure enough is consumed is key. Shop MegaFood supplements like Calcium & Magnesium, Balanced B Complex and Vitamin D3.

Ketogenic Diet (Keto)

Unless you are living under a rock, you already know what the keto diet is. But for you rock-dwellers, the keto diet is a very low-carb, high-fat and moderate-protein diet. Following this diet may result in many positive outcomes, including weight loss, lowered triglycerides and improved cognitive function in certain situations.

But cutting carbs means cutting fruit servings. And since fruit is rich in many important vitamins and minerals, unfortunately, your body may be missing out on key nutrients with this limitation.

Vitamin C is an essential nutrient, meaning that your body can’t make it and you need to get enough from your diet. Limiting fruit may mean limiting your vitamin C intake – a risky deficiency that could result in bleeding gums, rough skin and a weakened immune system. Shop MegaFood supplements Complex C, Daily C-Protect* Nutrient Booster Powder™ or Gummy C Defense.

Other nutrients may be a concern for those limiting grains, fruits, starches, dairy foods and other nutrient-dense foods. According to one study evaluating nutrient deficiencies in popular diets, those who followed a low carb diet similar to the keto diet had an intake lower than what is recommended for:

  • thiamin
  • pantothenic acid 
  • biotin
  • folate/ folic acid
  • vitamin D
  • vitamin E
  • chromium
  • copper
  • iodine

In a nutshell, following the keto diet can result in some great outcomes, but it can leave you with some nutrient gaps if you aren’t careful.

Key Takeaway

Vegan, Whole30 and keto are popular diets - and while they can result in some welcomed outcomes, they can also leave you missing certain nutrients. Filling potential holes in your diet by taking a high-quality multivitamin can help you meet all of your nutrient needs and help you be sure that you are giving your body the very best. Shop MegaFood multivitamins.