Food / Diets / Nutrients

In addition to obtaining energy from the three macronutrients, it is crucial for survival to have an adequate intake of essential nutrients, vitamins, and minerals. These vital food components are usually found in both natural and processed foods. Ensuring an adequate intake of each component presents a challenging and complex task for the supposed control system.
Berthoud et al. 2021 Int. J. Obes. 45: 2156-2168

According to a review of 121 articles, 14 foods are beneficial components in the nutritional index for gut microbiota (DI-GM): fermented dairy products, chickpeas, soybeans, whole grains, fiber, cranberries, avocados, broccoli, coffee, and green tea (beneficial components)
Kase et al. 2022 Curr Dev Nutr. 6(Suppl 1): 371

Red meat, processed meat, refined grains, and high-fat diets (≥ 40% of energy from fat) are harmful.
Kase et al. 2022 Curr Dev Nutr. 6(Suppl 1): 371

Food introduces foreign antigens. The immune system should recognize them as harmless. This leads to immune tolerance. Pathological responses to food can occur.
Tordesillas & Berin 2018 Clin Rev Allergy Immunol 55(2): 107-117

Nutrition and Human Health

Nutrition has a profound impact on human health. The antidiabetic potential of food-derived bioactive peptides and protein hydrolysates suggests that these substances could be beneficial in managing diabetes (Antony & Vijayan 2021 Int. J. Mol. Sci. 22: 9059).

The amount, solubility, and complex-branched form of natural dietary fiber might exert optimum effects similar to those found in whole-food products (Antony & Vijayan 2021 Int. J. Mol. Sci. 22: 9059).

Macronutrient Recommendations

Humans should derive:

• 20–35% of their total energy intake from fat


• 45–65% from carbohydrates


• 15–25% from protein

Venn 2020 Nutrients 12: 2363

Nutrient Signaling and Biological Responses

Nutrient recognition and signal transmission are an essential part of the reward system, which shapes preferences for the associated tastes of foods. This occurs via a variety of sensors in the gastrointestinal tract and the vagal pathways, which relay information about ingested nutrients to the brain. Sodium-Glucose Transport Protein (SGLT1) as an intestinal sugar sensor plays a crucial role in sugar conditioning. However, the key sensors for fat are less well-defined, although G-Protein Coupled Receptor 40 (GPR40) and G-Protein Coupled Receptor 120 (GPR120) fatty acid sensors have been suggested as possibilities.
Berthoud et al. 2021 Int. J. Obes. 45: 2156-2168

Enteroendocrine cells (EECs) and Enterochromaffin Cells (EC) integrate nutrient signals in the gut with biological responses, leading to the production of several substances
Rezzani et al. 2022 Int. J. Mol. Sci. 23: 3758

Sugar and fat are essential nutrients. Consequently, animals have evolved taste-signaling pathways that detect and respond to sweet and fat stimuli, leading to appetitive and consummatory behavior
Zhao et al. 2003 Cell 115: 255-266;
Berthoud et al. 2021 Int. J. Obes. 45: 2156-2168

Impact of Industrialization on Nutrition

Human nutrition has been dramatically changed by industrialization (Collins & Belkaid 2022 Immunity 55: 210-223). This shift has led to:

• Constant and often excessive consumption of calories


• Exposure to foods derived from chemically managed animals and produce


• High intake of processed foods with preservatives, additives, and high levels of sugar, fat, and salt

This dietary shift has contributed to a rise in overweight and obesity rates, particularly in developed countries (Monteiro et al. 2013 Obes. Rev. 14 (suppl 2): 21-28; Snir et al. 2015 PLoS One 10: e0131422; Sonnenburg & Sonnenburg 2019 Science 366: eaaw9255).

Comparison of Weight Trends

Only 2–5% of today's hunter-gatherers are overweight, and less than 1% are obese (Kirchengast 1998 Ann. Hum. Biol. 25: 541-551; Walker et al. 2006 Am. J. Hum. Biol. 18: 295-311; Gurven et al. 2013 PLoS One 8: e55679; Remis & Jost Robinson 2014 Am. J. Phys. Anthropol. 154: 365-375).

In contrast, in developed countries like the United States, 74% of people are overweight, and about 40% are obese (Hales et al. 2020 NCHS Data Brief 360: 1-8; Malik et al. 2020 Nat. Rev. Endocrinol. 16: 615-616). This trend is increasing worldwide with increasing industrialization (Malik et al. 2020 Nat. Rev. Endocrinol. 16: 615-616).

Traditional Diets

The traditional diet in rural Africa was primarily low in fat and animal protein and rich in starch, fiber, and plant polysaccharides (Wan et al. 2020 Gut Microbes 11: 603-609).

Gender Differences in Food Preferences

Gender exerts an important influence on food preferences (Barrea et al. 2019 Nutrition 62: 7-17). Compared with females, male participants presented higher levels of TMAO (p<0.001), lower adherence to the Mediterranean diet (p=0.017), higher energy intake, consumed a greater quantity of animal proteins, carbohydrates, and n-3 PUFA, and lower plant proteins and n-6 PUFA (Barrea et al. 2019 Nutrition 62: 7-17).

Importance of Plant-Based Foods

Plants in the form of fruits, vegetables, and cereals are major components of the human diet (Kaoutari et al. 2013 Nat. Rev. Microbiol. 11: 497-504).

Conclusion

Nutrition is fundamental to human health (GBD 2017 Diet Collaborators 2019 Lancet 393: 1958-1972). However, changing headlines contain conflicting information about whether individual foods (e.g., butter, eggs, meat), nutrients (e.g., saturated fats, cholesterol, sodium), or dietary habits (e.g., Mediterranean or ketogenic diets) lead to improved, worsened, or unchanged health.

There is broad expert consensus that Western diets with a high proportion of highly processed foods are harmful and that switching the population to mainly minimally processed foods would likely bring significant health improvements (Katz & Meller 2014 Annu. Rev. Public Health 35: 83).

However, detailed questions about optimal human nutrition or physiological mechanisms remain open. Rigorous controlled nutritional studies would help answer such questions (Ioannidis 2013 BMJ 347: f6698; Nissen 2016, Ann. Intern. Med.164: 558).

see also:
Food Allergy (FA) / Food Sensitivity
Leafy Green Vegetables
Oral tolerance