Portuguese 
Spanish 
7 min of reading 
0 comments 
Research simulated human digestion and revealed that not all minerals present in cashew nuts and Brazil nuts are available for absorption
A study conducted at the Federal University of São Paulo showed that eating mineral-rich nuts does not mean that the body will absorb all these nutrients. The research evaluated the bioaccessibility of minerals in cashew nuts and Brazil nuts, also known as Brazil nuts.
According to the FAPESP Agency, the experiment simulated stages of human digestion in the laboratory and analyzed four minerals considered important for the body: copper, magnesium, manganese, and zinc. The aim was to understand how much of these elements are released during the digestive process and potentially available for intestinal absorption.
The result is noteworthy because nuts often appear on lists of nutritious foods, especially for containing healthy fats, fibers, vitamins, and minerals. But the study reinforces an essential point of nutrition, the total amount of nutrients in the food is not equal to the amount the body can use.
-
FBI sets up a “fake city” with a hospital, hotel, houses, market, traffic lights, and data center to train agents against cyberattacks as if a digital crisis were truly happening.
-
New technology starts monitoring 300,000 hectares in Mato Grosso do Sul in an initiative by Suzano that combines sensors, continuous monitoring, and advanced data analysis, allowing for quick identification of threats and enhancing regional environmental protection.
-
Thai girl sees hornbills on a school trip, discovers that species are declining and creates artificial nests with repurposed plastic; at 17, the project engages communities, protects chicks, and wins an international environmental award for young innovators.
-
A rare gas cuts through the hot springs in Zambia and reveals a deep fault that may penetrate the crust down to the Earth’s mantle.
The discovery does not turn nuts into dietary villains. On the contrary, experts and health organizations continue to treat nuts as useful foods in a varied diet, but the research indicates that they should be seen as a complement, not as the sole source of certain minerals.
Unifesp study analyzed cashew nuts and Brazil nuts in simulated digestion
The research was conducted by scientists from Unifesp, with support from FAPESP, and focused on two nuts widely consumed in Brazil. According to the FAPESP Agency, samples of cashew nuts and Brazil nuts were evaluated, foods associated with high nutritional value and the presence of minerals.
The researchers first measured the total concentration of the elements in the samples. Then, they subjected the material to an in vitro test, a laboratory procedure that reproduces conditions of the human digestive system, such as temperature, agitation, pH, and the presence of enzymes.
This type of test does not show exactly how much a person would absorb after eating nuts in a real meal. Nevertheless, it helps estimate the fraction of minerals that detach from the food during digestion and become available for possible absorption in the intestine.
The study was coordinated by chemist Angerson Nogueira do Nascimento, associate professor at Unifesp, in partnership with the group of Professor Dário Santos Junior, from the Institute of Environmental, Chemical and Pharmaceutical Sciences of the university, at the Diadema campus.
Body released little magnesium and copper in part of the analyzed nuts
The numbers presented by the research help explain why the difference between “having mineral” and “utilizing mineral” is important. In the case of cashew nuts, about 56% of the copper and 52% of the magnesium present in the food became available after simulated digestion.
In Brazil nuts, the bioaccessibility was lower for magnesium. According to the results published by Agência FAPESP, approximately 50% of the copper and 28% of the magnesium became available after the digestion process in the laboratory.
Meanwhile, manganese and zinc appeared in insufficient quantities for reliable measurement in the analyzed fraction. This does not mean that these minerals do not exist in the nuts, but that, under the experiment conditions, they were below the detection limit of the technique used by the researchers.
The central conclusion is that the evaluated nuts may contain copper, magnesium, manganese, and zinc in their composition, but only part of these minerals becomes potentially available after simulated digestion. This detail changes the way to interpret labels, nutritional tables, and lists of “mineral-rich” foods.
Bioaccessibility is not the same as bioavailability
One of the most important points of the study is the difference between bioaccessibility and bioavailability. Bioaccessibility indicates the fraction of the nutrient that is released from the food during digestion and is in a condition to be absorbed.
Bioavailability goes further. It considers what is effectively absorbed and used by the body, taking into account processes like transport, metabolism, storage, and excretion. Therefore, a mineral may be bioaccessible, but not necessarily fully utilized by the body.
According to Agência FAPESP, bioaccessibility can be studied through laboratory assays. Bioavailability, however, requires more complex studies, usually involving animals or humans, which involves higher costs and specific ethical approval.
This distinction is relevant because consumers often associate nutritional value only with the total composition of the food. The study shows that a more complete evaluation also needs to consider how the food behaves within the digestive process.
Minerals have important functions but depend on a varied diet
The minerals evaluated in the study fulfill relevant functions in the human body. Copper is involved in processes related to energy production, iron metabolism, tissue formation, and immune system functioning, according to technical materials from the Office of Dietary Supplements, linked to the National Institutes of Health in the United States.
Magnesium also plays a broad role. It participates in hundreds of biochemical reactions, including muscle and nerve function, glucose control, blood pressure, energy production, and bone health. Therefore, its presence in the diet is considered important at different stages of life.
Zinc is related to the immune system, protein and DNA synthesis, healing, and growth. Manganese, in turn, acts as a cofactor for enzymes involved in metabolism and bone formation, in addition to participating in antioxidant mechanisms.
Even so, the practical message is not to consume nuts in excess to try to compensate for the low release of minerals. The safest guidance is to maintain a diversified diet, with different sources of nutrients, rather than relying on a single food.
Nuts remain useful in the diet, but with care in nutritional interpretation
The Ministry of Health classifies nuts, walnuts, almonds, and peanuts as oilseeds that can complement meals and serve as small meals, as they require little or no preparation. These foods are associated with minerals, vitamins, fibers, unsaturated fats, and antioxidants.
The same guidance, however, warns about the care with versions added with salt or sugar, which become processed foods and should have limited consumption. In practice, this means that the best choice tends to be nuts without excess salt, sugar, or coatings.
The new study does not deny the nutritional benefits of nuts. It merely adds a layer of precision to the subject, showing that the value of a food should not be measured solely by the sum of the nutrients present in its composition.
This point also dialogues with food composition databases, such as the Brazilian Food Composition Table from USP. These tables are important for estimating nutrients present in foods, but bioaccessibility research helps to understand how much can be available after digestion.
Result reinforces that no food should be treated as an isolated solution
For those who consume nuts every day, the research does not indicate the need to abandon the habit. The main message is to avoid the idea that a handful of nuts, alone, ensures the supply of copper, magnesium, zinc, or manganese.
According to Agência FAPESP, the study’s coordinator himself argues that these foods can contribute complementarily to a balanced and diversified diet. In other words, nuts still have a place in the menu, but should not be treated as the exclusive source of minerals.
In daily nutrition, variety remains the most consistent strategy. Beans, whole grains, fruits, vegetables, legumes, seeds, meats, eggs, milk, and other foods can participate in the supply of nutrients, according to individual needs and the guidance of health professionals.
The finding also helps combat a simplified view of nutrition. Foods do not function as isolated capsules of nutrients, and the human body does not absorb everything automatically. Digestion, food combination, quantity consumed, and individual characteristics can influence utilization.
What changes for the consumer after the research
The main change is in how nutritional information is read. When packaging, tables, or reports state that a certain food has a lot of magnesium, zinc, or copper, it does not mean that 100% of that mineral will be utilized by the body.
In the case of nuts analyzed by Unifesp, the study showed that part of the copper and magnesium became available after simulated digestion, while manganese and zinc could not be measured confidently in the bioaccessible fraction. This is important information for consumers, nutritionists, researchers, and diet formulators.
It is also a warning against exaggerated promises about “superfoods.” Although nuts are nutritious and practical, none of them should be presented as an isolated solution for immunity, bones, energy, or mineral replacement.
The best reading is balanced: nuts can be part of a healthy diet, but their effect depends on the overall diet. As shown by the Unifesp research, what matters is not just what the food contains, but what the body can release and use after digestion.
Do you usually consume nuts thinking that the body utilizes all the minerals present in them? Leave your comment and tell us if this research changes how you view these foods in your daily life.
Be the first to react!