Common Nutritional Needs That May Be Overlooked on a Keto Diet

By Robert Silverman, DC, DACBN, DCBCN, MS, CCN, CNS, CSCS, CIISN, CKTP, CES, HKC, FAKTR

The keto diet is based on the idea that eating a fixed macronutrient breakdown of mostly healthy fats, high-quality protein in moderation, and restricted carbohydrates (less than 50 grams per day) provides your body with the fuel you need to lose body fat without hunger, weakness, and fatigue.¹ The reduction in carb intake puts your body into a metabolic state called nutritional ketosis.² Thanks to the diet’s many benefits, its popularity has grown. That growth has spurned new variations, such as the “dirty keto” diet, while illuminating potential nutritional deficiencies that must be addressed.

A closer look at dirty keto

Dirty keto follows the same macronutrient breakdown of fats, protein, and carbs as clean keto, except for one major difference: It doesn’t matter which foods those macros come from. So instead of choosing good, healthy fats like wild-caught salmon, grass-fed butter, and avocado, you eat a fast food burger (without the bun), processed cheese, and pork rinds. Will you lose weight by following the dirty keto diet? Yes. But there are remarkable health drawbacks you should be aware of, too—namely, the dirty keto diet is missing vital micronutrients like vitamins, minerals, and enzymes that are necessary to your overall health.

Furthermore, processed foods are usually high in sodium, which can lead to bloating and other GI discomfort.³ In my clinical practice, I’ve seen patients both regain the weight they’ve lost and experience more cravings and less satiety. Dirty keto foods can trigger these cravings and feelings of food withdrawal, leading to what’s known as the keto flu.⁵

Common nutritional deficiencies on the keto diet

Overall, choosing the clean keto diet is the better route if you want to minimize these undesirable side effects. However, even the clean keto diet may result in vitamin and nutrient deficiencies. Here are some common ones—and some diet based options that are available to support them.

Magnesium

Magnesium is an essential mineral that plays a critical role in human biochemistry and general health. Present in all cells of the body, magnesium serves as an enzyme cofactor in more than 300 biochemical reactions, including protein synthesis, muscle and nerve function, blood glucose maintenance, and blood pressure regulation.⁵ Magnesium is also necessary for glycolysis, which is the first step in converting carbohydrates into energy—playing a highly important role in the body’s ability to maintain healthy energy levels.⁶ In addition, magnesium contributes to the structural bone development and is necessary for the synthesis of DNA, RNA, and glutathione.⁶ It also plays a role in the active transport of calcium and potassium ions across cell membranes, critical to nerve impulse conduction, muscle contraction, neurological health, and cardiac function.⁶

Fiber

Fiber is paramount to our digestive health. As a type of carbohydrate, however, fiber is unsurprisingly scant in the diet of someone on keto. In this case, adding fiber through leafy green vegetables may be a good idea.  

Iron

Without iron, our cells cannot get oxygen. Iron is also responsible for hemoglobin formation and improving blood quality.⁷ Many people struggle to consume adequate amounts of iron in their standard diets. Iron-rich foods such as red meat, legumes, quinoa, turkey, and others may help avoid running low on this key micronutrient.  

Zinc

Zinc is involved in many aspects of cellular metabolism, it supports normal growth and development.⁸ Zinc can be found naturally in poultry, fish, and red meat.  

Electrolytes

Electrolytes are substances that are utilized by the body to create electrically charged fluids. Many bodily functions depend on electrolytes, especially in muscle and nervous system tissue. Major electrolytes found in the body include sodium, chloride, potassium, magnesium, calcium, phosphate, and bicarbonate. Some whole-food options to increase electrolytes are spinach, bananas, prunes, broccoli, and oranges.

Thiamin and folate

B vitamins—such as thiamin, folate, and a number of others—are indispensable for the body’s energy supply and for the optimal functioning of the muscles and nervous system.⁹ This group of water-soluble vitamins also stimulates the production of neurotransmitters.⁹ When you consume a low-carb diet such as keto, you might experience a deficiency in thiamin and folate.⁹

Vitamin C

Vitamin C promotes proper functioning of neurotransmitters and protects our cells from damage.¹⁰ Vitamin C is also needed for building connective tissue and promoting resistance to infection.¹⁰ A variety of low-carb foods contain vitamin C, including kale, bell peppers, broccoli, Brussels sprouts, as well as most fruits. 

Compared to the Standard American Diet, the keto diet is not only safe for helping overweight people lose weight, recent studies have also demonstrated a variety of health benefits that don’t include just weight loss.^11,12 However, followers of the keto diet should be prepared to address possible vitamin and nutrient deficiencies—namely, deficiencies in magnesium, fiber, iron, zinc, electrolytes, thiamin, folate, and vitamin C. To maintain healthy levels of these vital nutrients, consult your Functional Medicine practitioner to ascertain the appropriate dietary changes that suit your individual health needs.

Dr. Silverman is a paid consultant and guest writer for Metagenics.

References:

1. Volek JS et al. Nutr Met. 2004;1:13.
2. JAMA. 2018;319(3):215-217.
3. Haidong Zhu et al. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3934330. 2014;133(3):e635–e642. Accessed May 9, 2019.
4. Institute of Medicine (US) Standing Committee on the Scientific Evaluation of Dietary Reference Intakes. Washington (DC): National Academies Press (US); 1997.
5. https://www.healthline.com/nutrition/keto-flu-symptoms Accessed May 9, 2019.
6. Lukaski HC. Nutrition. 2004;20(7-8):632-644.
7. National Institutes for Health, Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Iron-Consumer/ Accessed May 9, 2019.
8. National Institutes for Health, Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Zinc-Consumer/ Accessed May 9, 2019.
9. National Institutes for Health, Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/Thiamin-Consumer/ Accessed May 9, 2019.
10. National Institutes for Health, Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminC-Consumer/ Accessed May 9, 2019.
11. Hussein MD et al. Exp Clin Cardiol. 2004;9(3):200–205.
12. Hussain TA et al. Nutrition. 2012;28(10):1016-1021.