Realidad

Los granos enteros son seguros para el consumo, aunque pueden contener pequeñas cantidades de arsénico, un elemento natural presente en el suelo, el agua y el aire que las plantas pueden absorber mientras crecen. Existen dos tipos: arsénico inorgánico (más perjudicial) y arsénico orgánico. La exposición crónica al arsénico inorgánico a través de la dieta o del agua puede aumentar el riesgo de cáncer de piel, vejiga y pulmón.¹

Sin embargo, organismos de evaluación del riesgo, como la Autoridad Europea de Seguridad Alimentaria (EFSA), controlan los niveles de exposición de los consumidores al arsénico para ayudar a la Comisión Europea y a los Estados miembros a garantizar que las concentraciones de arsénico en los granos enteros en Europa se mantengan dentro de márgenes seguros.

Mito

Es cierto que los granos enteros pueden contener un poco más de arsénico que los refinados, ya que este elemento puede acumularse en las capas externas (el salvado y el germen), que se eliminan durante el proceso de refinado.

El arroz, en particular, suele presentar niveles más altos de arsénico debido a su forma de cultivo: a diferencia de otros cereales, el arroz se cultiva habitualmente en campos inundados, donde el arsénico presente de forma natural en el suelo y en el agua de riego es más fácilmente absorbido por la planta.²

Para proteger a los consumidores de una exposición excesiva, la normativa de la Unión Europea establece un nivel máximo de arsénico en el arroz: 0,25 mg/kg para el arroz integral y 0,15 mg/kg para el arroz blanco.

Para hacerse una idea de la magnitud: tomando como referencia el punto de partida de la EFSA, que indica la dosis más baja que podría asociarse a un mayor riesgo de cáncer de piel tras la exposición al arsénico inorgánico (0,06 µg/kg de peso corporal al día), y aplicando los niveles máximos de arsénico inorgánico establecidos para el arroz, una persona adulta de 70 kg alcanzaría ese valor de referencia conservador tras consumir aproximadamente 17 g diarios de arroz integral (o 28 g diarios de arroz blanco).

Sin embargo, conviene recordar que se trata de un valor de referencia para la evaluación de la seguridad normativa, no de una recomendación de consumo diario. Su propósito es orientar las decisiones de salud pública, no indicar a una persona que “no debe comer más de 17 g de arroz al día”. Además, las autoridades reguladoras incorporan amplios márgenes de seguridad en los límites máximos para minimizar cualquier posible riesgo para la salud.

Pasarse a los granos refinados no es la solución, ya que supone perder la fibra, las vitaminas y los minerales que hacen que los granos enteros sean nutritivos y estén ampliamente recomendados. Además, existen formas eficaces de reducir la exposición al arsénico del arroz:

• Hervir el arroz previamente en una proporción de 4 partes de agua por 1 de arroz durante 5 minutos, escurrirlo, añadir agua limpia en la misma proporción y cocinar hasta que el agua se absorba.³
• Variar el consumo de granos, incorporando opciones como la quinoa, la avena, la cebada, el bulgur o el trigo integral, que en general presentan niveles de arsénico más bajos que el arroz.

Por qué parece cierto (aunque no lo sea)

Este mito distorsiona el concepto de riesgo científico, dando a entender que, como el arsénico puede ser perjudicial en dosis altas, los granos enteros no son seguros para el consumo diario. En realidad, los niveles en Europa están muy por debajo de cualquier umbral de riesgo.

Otro error es la llamada “falacia de la falsa elección”: presentar solo dos opciones posibles, obligando a elegir entre extremos en lugar de considerar alternativas intermedias. Al centrarse únicamente en un posible riesgo (el arsénico) e ignorar los beneficios generales para la salud (fibra, vitaminas y minerales), este mito crea una falsa disyuntiva.

Realidad

Los granos enteros son seguros para el consumo y, como todos los alimentos, están estrictamente regulados en cuanto a residuos de pesticidas. Los pesticidas se utilizan habitualmente en la agricultura para proteger los cultivos de plagas y enfermedades. Pueden quedar pequeños restos en los alimentos tras la cosecha, pero estos niveles se controlan y regulan rigurosamente en Europa por los Estados miembros y organismos como la Autoridad Europea de Seguridad Alimentaria (EFSA).

Además, las autoridades reguladoras incorporan amplios márgenes de seguridad en los límites máximos establecidos para garantizar niveles de ingesta seguros. Los granos enteros siguen siendo un elemento clave de una dieta saludable, ya que aportan nutrientes esenciales que se pierden con el refinado, como la fibra, el hierro, el magnesio y las vitaminas del grupo B.

Consulta aquí la base de datos de los pesticidas autorizados en la UE y los niveles de residuos en distintos productos alimentarios.

Mito

Si bien es cierto que los granos enteros pueden tener ligeramente más residuos que los granos refinados, ya que las capas externas del grano (el salvado y el germen) se mantienen intactas y es ahí donde se encuentran las concentraciones más altas de residuos de plaguicidas, esto no significa automáticamente que contengan niveles dañinos.⁴ La EFSA concluyó que el riesgo para la salud del consumidor por la exposición estimada a los residuos de plaguicidas en los alimentos analizados es bajo.⁵ La Unión Europea cuenta con algunas de las normativas sobre plaguicidas más estrictas del mundo, incluidas las relativas a los niveles máximos de residuos (LMR) —la cantidad más alta de residuo de plaguicida permitida legalmente en o sobre los productos alimentarios—, que se revisan y actualizan periódicamente. Los productos alimentarios que superan los LMR están sujetos a sanciones legales y medidas de control. El posible riesgo derivado de los plaguicidas en los granos enteros no supera los beneficios nutricionales bien conocidos de su consumo.⁶

Por qué parece cierto (aunque no lo sea)

Este mito parte de una pequeña verdad —que los granos enteros suelen contener ligeramente más residuos de plaguicidas que los refinados, ya que conservan las capas externas— y la convierte en una afirmación generalizada y engañosa. Sugiere que evitar los granos enteros es más seguro, ignorando tanto los beneficios para la salud que aportan como los controles de seguridad que ya existen.

También recurre al miedo, insinuando que cualquier residuo de plaguicida es perjudicial, sin considerar la dosis. En realidad, los plaguicidas están estrictamente regulados y los niveles de residuos en los granos producidos en la UE se mantienen muy por debajo del umbral de preocupación. Estas normativas existen precisamente porque los plaguicidas son tóxicos en dosis elevadas, pero en las cantidades controladas que se encuentran en los alimentos no suponen un riesgo para la salud. Además, los plaguicidas desempeñan un papel importante en garantizar la seguridad, la integridad y la disponibilidad de los alimentos al proteger los cultivos frente a plagas y enfermedades.

El mito también se apoya en la falacia de que “lo natural es más seguro”, que asume erróneamente que todo lo artificial (como los plaguicidas sintéticos) es automáticamente peligroso. En la práctica, lo que realmente importa es que los niveles de residuos se mantengan dentro de los márgenes de seguridad autorizados, establecidos para proteger a los consumidores.

Realidad

Los granos enteros son muy beneficiosos para el sistema digestivo y la salud en general. Son ricos en fibra, un componente esencial para nuestro microbioma intestinal —los billones de bacterias beneficiosas que habitan en nuestros intestinos—. Estas fibras sirven de alimento para esas bacterias buenas, ayudándolas a prosperar y a producir compuestos beneficiosos como los ácidos grasos de cadena corta (AGCC). Estos protegen nuestra salud al mejorar la sensibilidad a la insulina y mantener niveles más bajos de glucosa y lípidos en sangre. A largo plazo, esto puede favorecer un mejor equilibrio energético, lo que a su vez ayuda a prevenir enfermedades cardiovasculares, la obesidad y la diabetes tipo 2.^7,8,9

Los granos enteros son más complejos que los refinados y se promueven como parte de una dieta saludable y sostenible, en gran medida por su alto contenido en carbohidratos no digeribles (fibras alimentarias) y por sus mayores niveles de vitaminas, minerales y otros nutrientes.¹⁰

Mito

La idea de que los granos enteros son una causa frecuente de hinchazón y gases suele deberse al hecho de que contienen fibras y ciertos carbohidratos que no se digieren completamente en el intestino delgado. Cuando estos llegan al intestino grueso, las bacterias intestinales los fermentan, lo que puede producir gases. Sin embargo, este proceso natural suele ser una señal de que las bacterias intestinales están haciendo su trabajo, no de que los granos enteros sean problemáticos en sí mismos.

Por qué parece cierto (aunque no lo sea)

La falacia aquí consiste en atribuir algo de forma errónea. El proceso natural de fermentación que se produce cuando las bacterias intestinales descomponen las fibras de los granos enteros se percibe equivocadamente como un efecto secundario negativo, cuando en realidad es beneficioso. Aunque algunas personas pueden experimentar molestias temporales al aumentar su consumo de fibra, estas suelen desaparecer a medida que el intestino se adapta. En personas con sensibilidades específicas, como el síndrome del intestino irritable (SII), ciertos componentes de los granos, como los fructanos, pueden desencadenar síntomas adversos.¹⁰ Sin embargo, para la mayoría de la población, los granos enteros son una parte importante de una dieta equilibrada. Si experimentas molestias digestivas persistentes o graves, consulta con un profesional sanitario (por ejemplo, tu médico de cabecera o un dietista/nutricionista titulado) para recibir asesoramiento personalizado.

Antes de eliminar los granos enteros de tu dieta, hay algunos consejos y trucos que puedes poner en práctica para ayudar a tu intestino a adaptarse y tolerar mejor estos alimentos ricos en fibra, reduciendo la hinchazón:

• Introduce gradualmente los alimentos ricos en fibra y reparte su consumo a lo largo del día. Se trata de entrenar al intestino, aumentando poco a poco la cantidad de fibra, para facilitar la adaptación a una dieta con más fibra.
• Evita tragar aire de más tomándote tu tiempo para comer. Come despacio, disfruta de cada bocado y mastica bien los alimentos.
• Mantén tu cuerpo activo e hidratado. La actividad física regular ayuda a mantener en movimiento el sistema digestivo, lo que reduce la probabilidad de molestias. Y no olvides mantenerte bien hidratado bebiendo suficiente agua.

Fact

Anti-nutrients are chemicals that are found in plant-based foods that can interfere with how your body absorbs nutrients. In whole grains, the main ones are lectins, oxalates, phytates, and tannins. Although evidence is limited, some suggested implications of these anti-nutrients include altered gut function and inflammation (lectins), reduced absorption of calcium (oxalates), reduced absorption of iron, zinc, and calcium (phytates), and iron (tannins).

But here’s the important part: in a balanced diet, this effect is minimal and doesn’t make whole grains “nutritionally worthless.” In fact, whole grains contribute significantly to daily nutrient intakes, and their benefits far outweigh any potential minor reduction in mineral absorption.¹¹

Myth

The myth suggests that compounds like phytates, lectins, oxalates, and tannins in whole grains hinder nutrient absorption, making them unhealthy. This oversimplified view, for example, ignores the difference in how these compounds behave in isolation versus within a complex food matrix:

1. Context matters. Concerns about antinutrients largely arise from studies using isolated compounds (e.g., not as part of a food), very high amounts, unprocessed forms (e.g., raw grains), or in animal models or in vitro, which don’t accurately reflect real-world human consumption patterns. Human trials on whole, cooked foods generally don’t show significant health risks from these compounds.
2. Processing reduces antinutrients naturally. Cooking, soaking, sprouting, germinating, and fermenting all lower antinutrient (e.g., phytate) levels. Bread, for example, contains far less phytate than the raw grain.
3. Antinutrients may even have health benefits. Some studies suggest they act as antioxidants that can protect against various chronic diseases and even have anti-cancer properties. For example, tannins are well-known antioxidants.

Why it feels true (even when it’s wrong)

The misconception relies on the fallacy of isolation. While antinutrients can bind minerals in a lab test, that doesn’t mean eating whole grains leads to deficiencies in real-life diets, especially in Europe, where diets are highly diverse. Research from large populations eating whole grains over multiple years and trials of people replacing refined grains with whole grains consistently shows that whole grains improve overall nutrient intake and health outcomes.^12,13

Fact

Whole grains are rich in fibre, which supports digestive health. But for some people with Irritable Bowel Syndrome (IBS) or other gut sensitivities, certain grains can trigger symptoms like bloating, discomfort, or changes in bowel habits. Especially wheat, rye, and barley have been linked to these symptoms in sensitive people.¹⁴

Guidelines recommend that it may be helpful to limit the intake of high-fibre foods (such as whole grain or high-fibre flour and breads, cereals high in bran, and whole grains such as brown rice) for those with IBS, but that doesn’t mean all whole grains are off the table.¹⁵ A gluten-free diet is often used to alleviate symptoms for those with IBS, but gluten isn’t always what causes the discomfort. Research suggests that symptom relief is achieved not from removing gluten specifically, but from excluding wheat itself, indicating that other wheat components—such as fructans, amylase-trypsin inhibitors, and lectins—are likely responsible for triggering digestive discomfort.¹⁴

Many people with IBS tolerate other nutritious whole grains such as spelt, oats, quinoa, rice, and corn. Spelt bread, for example, contains much lower levels of fructans than standard wheat bread. Observe which grains cause symptoms for you, identify the quantity of these products that trigger discomfort, and try to keep as much variety in your diet as possible.

Myth

It’s a common belief that people with IBS should cut out all whole grains, especially those containing gluten. While some people do report relief after avoiding wheat-based products, studies show that not everyone benefits from going gluten-free. In fact, many IBS patients who cut out gluten may actually be responding to the reduction of wheat and its other components, not gluten itself. Avoiding all whole grains can unnecessarily restrict the diet and lead to lower fibre and nutrient intakes, which may worsen gut health in the long run.

Why it feels true (even when it’s wrong)

This myth oversimplifies a complex condition. It assumes that because wheat may cause symptoms, all grains must be harmful. In reality, tolerance is highly individual: some people may react strongly to wheat but can enjoy oats, rice, quinoa, or spelt without problems.

Another fallacy is focusing solely on gluten as the “villain.” Research shows that other wheat compounds, like fructans, are often the real triggers for IBS symptoms. By blaming gluten alone, people may unnecessarily adopt restrictive diets that cut out valuable whole grains that could otherwise support digestive health.

Fact

Whole grains contain all three parts of the grain: the bran, germ, and endosperm. This makes them higher in fibre, vitamins, and minerals than refined grains and they also help to reduce our risk of developing chronic diseases. That’s why dietary guidelines across Europe recommend swapping white, refined products for whole grain versions.

But here’s the catch: a darker colour doesn’t guarantee a product is whole grain. Bread, crackers, or cereals can look brown simply because of added molasses, malt, or caramel colouring. True whole grain products can be identified by:

• Ingredients list: if “whole” or “whole grain” are before the name of the cereal (like “whole wheat pasta”) and if whole grains are listed as the first or second ingredient (after water), you can usually consider it a whole grain food.
• Logos and symbols: in some countries, like Denmark, the whole grain logo, or in Nordic countries, the Keyhole symbol, help identify healthier whole grain options.
• National rules: in Belgium and the Netherlands, for example, bread labelled as “whole grain” must be made entirely from whole grain flour.

Another easy trick? Use the 10:1 carbohydrate-to-fibre ratio: for every 10 g of carbs, a product should have at least 1 g of fibre.

Myth

A brown colour doesn’t guarantee it’s a whole grain product. In fact, they may still use mostly refined flour. Bread can be made mostly from refined white flour and simply coloured brown with molasses or caramel. Likewise, products described as “brown,” “multi-grain,” or “100% wheat” often look wholesome but may still lack the full benefits of whole grains.

Why it feels true (even when it’s wrong)

This myth falls into the trap of visual bias: judging healthiness based on colour. Brown bread looks “healthier” than white bread, so it’s easy to assume it’s whole grain. But colour can be misleading. What really matters is whether the product contains the entire grain kernel, not whether it looks dark.

Fact

Gluten is a protein found in wheat, barley, and rye. That means whole wheat bread, whole grain barley, and whole rye products, and any other whole grain products containing these grains all contain gluten. These should be avoided by people with coeliac disease or gluten sensitivity.

But many whole grains are naturally gluten-free, including: corn, rice (brown, red, black, and wild varieties), quinoa, buckwheat, millet, amaranth, teff, sorghum, and certified gluten-free oats. These gluten-free grains are safe and nutritious options that add variety, flavour, and important nutrients like fibre, vitamins, and minerals to your diet.

Unless you have a diagnosed gluten-related condition, there’s no evidence that cutting out gluten is healthier for you. In fact, some gluten-free products contain more sugar, fat, or salt than their regular counterparts.

Myth

Not all whole grains are high in gluten. There are many different whole grains to choose from and include as part of your diet. This myth lumps all whole grains together, assuming they all act like wheat. While wheat, rye, and barley do contain gluten, many other grains don’t. By painting all whole grains with the same brush, this myth wrongly encourages people to avoid a wide variety of safe and nutritious foods.

Why it feels true (even when it’s wrong)

This myth makes the mistake of overgeneralisation, taking the fact that some grains contain gluten and applying it to all grains. In reality, gluten is only found in a few types. Avoiding all whole grains because of gluten is like avoiding all fruit because you’re allergic to strawberries—it cuts out far more than necessary.

Fact

Carbohydrates are our body’s main energy source, fuelling the brain, muscles, and all cells. Eating carbs doesn’t automatically cause weight gain. What matters is the overall balance between calories in and calories out.

Whole grains provide fibre, vitamins, minerals, and protective plant compounds that support satiety, stable energy, and long-term health. Fibre helps us feel fuller for longer periods after a meal. This means we eat less food, which could lead to a reduction in overweight and obesity. There are data to suggest that eating whole grains can lead to slightly reduced body weight in obese/overweight populations compared to non-whole grain diets.¹⁶

International agencies including the European Food Safety Authority (EFSA) recommend that adults get 45–60% of their daily calories from carbohydrates, with as little added sugar as possible and at least 25 g of dietary fibre per day.¹⁷ Cutting out whole grains runs directly against these evidence-based recommendations.

Myth

Whole grains don’t automatically cause weight gain because they’re high in carbs. This myth is reinforced by the popularity of low-carb and keto diets. Advocates of such diets argue that carbs drive weight gain by increasing insulin, which promotes fat storage. But scientific evidence doesn’t support this theory:¹⁸

• Large studies show that low-carb diets aren’t more effective than balanced diets for long-term weight loss.
• Weight loss on keto or low-carb diets is often due to calorie restriction and water loss (from depleted glycogen stores), not fat loss.¹⁹ Once carbs are reintroduced, weight usually comes back.

While refined carbs and sugary drinks can contribute to excess calories, whole grains are a different story. They provide fibre, vitamins, and minerals that help regulate appetite and support healthy digestion.

Why it feels true (even when it’s wrong)

The “carbs = fat gain” myth relies on the carbohydrate–insulin model, which selectively cites evidence and ignores the bigger picture. Yes, insulin helps store fat temporarily, but fat gain only occurs if total calories consistently exceed what the body uses. Studies show that when calorie and protein intake are controlled, low-carb diets don’t lead to greater fat loss than diets with more carbohydrates.^20,21

Another fallacy is confusing water loss with fat loss. The rapid results many see on keto come mostly from glycogen and water being flushed out, not actual fat reduction. Over time, weight loss typically plateaus, and health risks may increase due to nutrient deficiencies and whole grains being displaced with foods high in saturated fat.²²

Finally, this myth fails to distinguish between refined carbs (like sugary drinks and white bread, which are linked to weight gain) and nutritious carbs (like whole grains, fruits, and legumes, which support healthy weight and lower disease risk). In fact, diets low in whole grains are the leading dietary risk factor for ill-health, disability, and early death in Europe.²³

Fact

Inflammation isn’t always a bad thing. In fact, it’s the body’s natural defence mechanism: when you cut your finger or fight off an infection, inflammation helps heal wounds and protect against harmful microbes. The problem comes when inflammation doesn’t switch off and becomes chronic. Chronic, low-grade inflammation has been linked to obesity, cancer, and cardiovascular diseases.²⁴

Multiple large-scale studies demonstrate that eating whole grains lowers markers of chronic inflammation:²⁵

• A systematic review of randomised controlled trials found that eating whole grains significantly reduced C-reactive protein (CRP) levels in 10 out of the 32 studies. CRP is one of the most reliable measures of inflammation.
• Whole grain intake has also been linked to lower levels of IL-6 and TNF-α, two signalling proteins (cytokines) that the immune system releases to trigger and maintain inflammation. However, results for these markers are somewhat less consistent than for CRP.

Why? Whole grains are rich in fibre, phenolic acids, and other bioactive compounds. These not only improve gut microbiota but also produce metabolites that help dampen inflammatory pathways.²⁶

Myth

Whole grains don’t cause inflammation. This myth often points to “anti-nutrients” like gluten or lectins, claiming they irritate the gut and set off inflammation. While some people with coeliac disease or wheat allergy must avoid gluten, for the vast majority, these claims are misleading. In normal amounts and as found in whole, cooked grains, lectins and phytates are not harmful—and in many cases, they may even have protective health benefits.¹¹

By focusing only on theoretical risks, this myth ignores the strong evidence showing that whole grains reduce inflammation and promote long-term health.

Why it feels true (even when it’s wrong)

The idea that whole grains “cause inflammation” cherry-picks isolated lab studies on compounds like gluten or lectins, and then generalises those findings to everyone. But human studies overwhelmingly show the opposite: higher whole grain intake is linked to lower inflammation and disease risk.

Another fallacy is confusing special cases with the rule. Yes, people with coeliac disease must avoid gluten-containing grains, but this doesn’t apply to the general population. As recommended by almost all dietary guidelines, whole grains are part of a healthy, balanced dietary pattern that helps promote overall health.

Fact

Whole grains, whether in a slice of whole grain bread, a bowl of oats, or a box of whole grain pasta, are consistently linked to better health outcomes. Research shows that eating 50 g of whole grains daily is linked to a 25% lower incidence of type 2 diabetes, 20% reduced risk of cardiovascular mortality, 12% reduction in cancer mortality, and a 15% decrease in total mortality.¹³ This holds true whether the grains come from a bag of brown rice, a packet of whole grain crackers, or a loaf of rye bread.

Yes, some whole grain foods are packaged and may fall under the NOVA “ultra-processed” (UPF) classification, which defines certain foods as containing little of no whole foods and that are formulations of ingredients made by a series of industrial processes and/or containing food additives. For example, many commercially produced whole grain breads contain additives to improve texture, taste, and shelf life. These additives may include emulsifiers, dough conditioners, and stabilisers – processed ingredients that are common in ultra-processed foods. All food additives have been thoroughly tested, classified as safe by the European Food Safety Authority (EFSA) and approved for use by the European Commission and Member States.

Myth

Avoiding all packaged whole grain foods because they’re ultra-processed could unnecessarily restrict your diet. While some UPFs may contribute to poor health outcomes, other UPFs can be nutrient-rich and fit into a balanced diet, such as whole grain bread, vegetable-based sauces, and (fortified, low-sugar) plant-based dairy alternatives. Certain groups, such as animal products, sauces, spreads and condiments, and artificially and sugar-sweetened beverages, have been found to be associated with increased disease risks, while other groups, such as breads and cereals, have been associated with lower disease risks.²⁷ This might be explained by the fibre content of such products. What matters most is what’s inside the package. For example:

• A loaf of whole grain bread with ingredients like whole grain flour, water, yeast, and a little salt can be an excellent source of fibre and nutrients.
• A box of fibre-rich whole grain cereal may help you reach the recommended 25 g of fibre per day.

A key to making more informed food choices is to check the ingredients list and the nutritional information: does it contain mostly whole grains, with limited added sugar, salt, and fat? If yes, it can absolutely fit into a balanced diet.

Why it feels true (even when it’s wrong)

This myth works through guilt by association: because some ultra-processed foods are linked to poor health outcomes, all foods in this category must be harmful. But nutrition science doesn’t work that way. The health effects of a food depend on its nutrient content, role in the diet, and overall dietary pattern, not simply whether it comes in a package or is “processed.” Dietary guidelines across Europe encourage eating more whole grains, including packaged versions like bread, pasta, or breakfast cereals, because they help fill fibre and other nutrient gaps in our diets.