Eating gluten-free: which nutrients might you be missing out on?

Whether you follow a gluten-free diet due to celiac disease, a wheat allergy, gluten sensitivity, or simply by personal choice, one question often comes up: "Am I at risk of missing out on certain nutrients?" The answer is not necessarily, though some nutrients do warrant special attention. Fortunately, with a varied and well-planned diet, it is entirely possible to meet your nutritional needs.

Why do certain nutrients require closer monitoring?

Two reasons explain why some people following a gluten-free diet may have insufficient intakes of certain nutrients.

1. Gluten-free products are often less nutritious.

Gluten-free breads, pastas, crackers, cereals, and other products are often made with refined flours and starches, such as white rice flour, potato starch, or tapioca. Compared to whole-wheat products, they often contain less fiber, protein, iron, and B vitamins. This does not mean you have to avoid them. You simply need to carefully read the Nutrition Facts tables and ingredient lists to choose whole-grain products that provide adequate nutritional value.

2. Reduced nutrient absorption (in people with celiac disease)

In people with celiac disease, gluten triggers an immune reaction that damages the villi of the small intestine. Damage to the intestine can reduce the absorption of several nutrients, such as vitamin D, calcium, and iron, thereby increasing the risk of deficiencies, particularly before diagnosis or if the intestine has not yet fully healed. A strictly gluten-free diet generally allows the intestine to gradually recover and improves nutrient absorption.

Nutrients requiring special attention

1. Fiber

Fiber is likely one of the nutrients most easily overlooked when adopting a gluten-free diet. Yet, fiber plays a vital role in health. In particular, it helps support gut microbiome health, promote regular bowel movements, increase satiety and provide more stable energy levels, contribute to the prevention of type 2 diabetes, help lower blood cholesterol, and reduce the risk of developing colorectal cancer. Fortunately, it is entirely possible to get enough fiber on a gluten-free diet by prioritizing foods naturally rich in fiber, such as fruits and vegetables, legumes, chia and flax seeds, nuts, quinoa, buckwheat, and certified gluten-free oats.

2. Protein

Protein is another nutrient worth paying attention to when following a gluten-free diet. Why? Because gluten is a protein naturally found in wheat, barley, and rye. When these grains are replaced to make gluten-free products, they are often swapped for ingredients like rice flour, potato starch, tapioca, or cornstarch, all of which are generally much lower in protein. Yet, protein plays a vital role in the body. It helps maintain and build muscle mass, supports the immune system, promotes tissue repair, increases satiety, and helps keep energy levels more stable between meals. However, this doesn't mean a gluten-free diet is necessarily low in protein; it just means it is important to include a source of protein in every meal and snack. Some excellent options include edamame, tofu and tempeh, eggs, and dairy products or fortified soy beverages. When choosing gluten-free grain products, take the time to compare labels. Some breads, cereals, and pastas are made with ingredients that are naturally higher in protein, such as legumes, quinoa, buckwheat, or soy, making them much better nutritional choices.

3. Iron

Iron is another nutrient that requires special attention when following a gluten-free diet. For people with celiac disease, the risk of deficiency is particularly high at the time of diagnosis, as intestinal damage can impair iron absorption. Furthermore, many gluten-free grain products are less enriched with iron than their wheat-based counterparts. Iron is essential for transporting oxygen in the blood. Insufficient intake can lead to fatigue, reduced concentration, shortness of breath during physical exertion, and, in some cases, anemia. To optimize your intake, make sure to regularly include iron-rich foods such as legumes, tofu, nuts and seeds, dark green vegetables (e.g., spinach), and whole grains (e.g., quinoa). Pairing these foods with a source of vitamin C (such as citrus fruits, strawberries, kiwis, or bell peppers) also helps improve the absorption of plant-based iron.

4. B-group vitamins

Certain B-complex vitamins, specifically folate (vitamin B9), thiamine (vitamin B1), riboflavin (vitamin B2), and niacin (vitamin B3), may be consumed in lower amounts on a gluten-free diet. This is because, unlike wheat flours, many gluten-free flours and products are minimally fortified, or not fortified at all, with these vitamins. B-complex vitamins play an important role in energy production, nervous system function, and blood cell formation. To ensure adequate intake, prioritize a varied diet that includes legumes, nuts and seeds, green vegetables, dairy products or fortified plant-based beverages, and whole grains (e.g., buckwheat, quinoa).

5. Calcium and vitamin D

Calcium and vitamin D work together to maintain strong bones and teeth. For people with celiac disease, these nutrients require special attention, as their absorption can be impaired when the intestine is damaged. Additionally, some people temporarily reduce their intake of dairy products after diagnosis due to transient lactose intolerance. To meet your needs, consider including calcium-rich foods such as dairy products or fortified plant-based beverages, tofu made with calcium sulfate, and fortified yogurts. Since dietary sources of vitamin D are limited, supplementation may be recommended for some individuals, based on the advice of their healthcare professional.

6. Zinc and magnesium

People following a gluten-free diet may sometimes consume less of these nutrients, particularly if their diet is low in whole grains, legumes, nuts, and seeds. Zinc and magnesium are two essential minerals involved in hundreds of bodily reactions. They play a key role in immune system function, wound healing, muscle function, and energy production. To ensure adequate intake, focus on a varied diet that includes legumes, nuts and seeds, whole grains (e.g., quinoa, buckwheat, rolled oats), and fruits and vegetables.

Gluten-free products should not form the basis of the diet.

When starting a gluten-free diet, it is natural to replace bread, pasta, or crackers with their gluten-free versions. However, it is just as important to discover foods that are naturally gluten-free, as these are often much more nutritious. Examples include legumes, quinoa, buckwheat, millet, brown rice, potatoes or sweet potatoes, fruits, vegetables, nuts, and seeds. By making these foods a larger part of your diet, it becomes much easier to get enough fiber, protein, vitamins, and minerals.

Key takeaways

A gluten-free diet can perfectly meet all nutritional needs. Regardless of the reason you are avoiding gluten, the goal is not just to choose gluten-free products, but also to build a varied, balanced diet rich in naturally nutritious foods.

• Nutrients requiring special attention: fiber, protein, iron, B vitamins, calcium, vitamin D, zinc, and magnesium.
• For people with celiac disease, this vigilance is all the more important due to intestinal damage.