White bread vs. whole grain bread: which is actually healthier?

White bread vs. whole grain bread: which is actually healthier?

A new analysis uncovers what really separates bread myths from evidence, and shows how both white and whole grain breads can support health when understood in context.

A study recently published in the journalNutrition Bulletinfocused on debunking the myths associated with white bread.

Global changes in wheat consumption

The increase in global wheat demand in 2025 will be driven primarily by low- and middle-income countries in Asia and Africa, which are experiencing rapid urbanization and industrialization. Most of these countries import wheat, which accounts for 25% of global wheat trade.

While overall global wheat consumption is increasing, traditional wheat-eating regions such as North America and parts of Europe are seeing stable or declining intake. For example, bread consumption in the UK fell from 950g per person per week in 1970 to under 500g per person per week in 2023.

Research shows that as society becomes wealthier, basic food consumption declines in favor of a more varied diet. Reduced wheat consumption also reflects growing concerns about the health effects of wheat-based foods.

Bread has long been a staple food and cultural staple around the world. Changes in crop species and processing methods are attracting widespread attention and fueling debates about organic versus conventional production, genetic modification, and traditional versus modern breads.

Critically assessing these issues is critical to providing evidence-based guidance to stakeholders and identifying gaps for future research. The authors note that many persistent myths surrounding bread are based on fragmented evidence and misunderstandings among the public, highlighting the need for clear communication.

How Milling Changes the Nutrition of Bread

Wheat grains are typically milled to separate the starchy endosperm from the nutrient-rich bran and germ (embryo), producing fine white flour. Grinding significantly reduces fiber, B vitamins, minerals and phytochemicals compared to whole grains because these nutrients are concentrated in the outer layers and in the germ.

The endosperm makes up about 83% of the wheat grain. Modern roller mills efficiently extract white flour, while traditional stone milling is less precise. Incorporating more bran into the milling process results in higher extraction flours, as was previously the case with National Flour in the UK.

Whole grain and whole wheat bread can differ in the fineness of the flour grinding, which affects the texture and appearance. Whole grain products contain endosperm, germ and bran in the same proportions as the intact grain, with only minor processing losses. In the UK, wholemeal flour includes all edible grains and wholemeal bread is made from 100% wholemeal flour.

Other breads mix white and whole wheat flour, use additional grains or seeds, or are fortified with fiber. Despite appearances, not all breads offer significantly higher nutritional value than white bread, so it's important to check the nutrition label. Differences in flour composition and proportions make it difficult to interpret health data for different types of bread.

The paper also highlights that the variability of whole grain product formulations leads to inconsistent results across studies.

Health effects of types of bread

The impact of bread on health depends on the type of bread, how much it is eaten and what it is eaten with. Regular consumption of whole grains can reduce the risk of chronic diseases such as type 2 diabetes, cardiovascular disease and colon cancer. These benefits are believed to be primarily due to the fiber and micronutrients in whole grains.

Unabsorbed carbohydrates, fiber and plant compounds in whole grains are fermented by gut microbes, resulting in a healthier gut environment and potentially reducing the risk of disease.

Previous studies have shown that eating whole grain bread can also help with weight control and promote healthier gut flora. Breads with coarsely ground grains or intact grains can also slow digestion and absorption, contributing to satiety. Sourdough or breads with coarsely ground grains may be denser, potentially helping to reduce consumption and therefore affecting energy absorption.

Phytochemicals in wheat, particularly phenols, can reduce inflammation and improve blood vessel function. This may be why whole grain bread is associated with fewer cardiovascular events.

While many believe that white bread raises blood sugar faster than whole grain or whole grain bread, studies show conflicting results. Some research suggests little difference, except when whole-grain bread is made with the grains intact, which can lower blood sugar spikes.

Gluten can cause celiac disease in susceptible people, and other proteins can cause wheat intolerance or allergies, although these are rare. Amylase-trypsin inhibitors (ATIs) enriched in white flour are associated with non-celiac wheat sensitivity.

Some worry that white bread could trigger more wheat-related reactions, especially because of its protein content. In addition to gluten, wheat also contains raffinose, which can worsen the symptoms of irritable bowel syndrome (IBS) by fermenting in the intestines, causing bloating and discomfort. However, fructans are the dominant FODMAPs in wheat and are found in higher amounts in whole grains than in white flour. The authors point out that individual tolerance varies greatly and that most people can safely eat both white and whole grain bread.

Reevaluation of factory-produced white bread

Despite decades of whole grain promotion, whole grain flour production has declined in the UK, while Denmark has seen success with nationwide campaigns. In some regions white bread remains more popular, for example in the UK 63% of adults consume white bread.

Generally, white bread is chosen for its affordability, convenience and taste. Even with some nutrient loss, it still provides a significant proportion of energy, fiber and folic acid in the British diet, particularly in lower income groups.

According to the Nova classification, prepackaged breads are often labeled as highly processed foods (UPFs), and in general, high UPF intake is associated with adverse health consequences. However, Nova has been criticized for oversimplifying food groups and not distinguishing between different UPF types.

Research has shown that health risks depend on overall nutritional quality and the specific ingredients in UPFs. Interestingly, a large study found that highly processed breads and grains are associated with a lower risk of certain diseases.

The new paper emphasizes that UPF status alone does not indicate that processed bread is inherently harmful. Instead, the authors emphasize that bread should be evaluated in the context of dietary habits and not just by its processing category.

Packaged breads also contain additives such as soy flour, rapeseed oil, ascorbic acid, emulsifiers, calcium propionate and enzymes. Most are naturally occurring or derived from natural sources, and all are tested for safety before approval.

Some concerns have been raised about emulsifiers and gut health, but current evidence is inconclusive and further research is needed to clarify any population-level effects. In the UK, factory-produced breads are classified as UPFs because they contain additives such as emulsifiers, while artisan breads are considered less processed.

Many countries require white bread flour to be fortified with minerals and B vitamins to replace nutrients lost during milling. In the UK, iron and calcium fortification results in white bread containing significant levels of these minerals, particularly when compared to wholemeal bread.

From 2026, British millers will have to add folic acid to white flour to prevent congenital disabilities. Fortification significantly increases folic acid intake from white bread, which is particularly beneficial for lower-income groups who rely more on white bread in their diet. Small mills and whole grain breads are exempt from this regulation.

The authors emphasize that fortification policy is an important public health tool and that white bread can make a meaningful contribution to nutrient supply.

Balanced conclusions on bread health

The current study found that while whole grain bread offers additional health benefits and should be encouraged, white bread remains a nutritious and affordable staple for many. Improving all types of bread through better ingredients and fortification is a practical way to support public health and ensure the nutritional needs of diverse populations are met.

The authors emphasize that white bread should not be viewed as inherently unhealthy and that further improving its nutritional profile may provide equal health benefits, particularly for lower-income households.

Overall, the study reinforces that balanced messaging and contextualized nutritional advice is essential to dispel misconceptions about bread and health.

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