Food is an essential part of human life. What we eat, how we cook, and where we get our nutrients from are foundational aspects of cultural expression and community health. A 2024 literature review in Foods a peer-reviewed open-access scientific journal on food science — highlights an alarming decline in the nutritional value of foods we typically consume, such as fruits and vegetables. 

According to this review, a combination of rising temperatures, chemical farming practices, compromised soil qualities, and inefficient food systems is causing people to be “overfed but undernourished due to consuming nutrient-poor diets.” 

Soil, seeds, and a warming Earth: causes and consequences of nutritional decline 

Foods that were once bursting with vital nutrients, such as apples, oranges, bananas, and broccoli, no longer pack the same nutrient-dense punch they did 50 years ago. Parsley, for example, which contains more vitamin C per 100 grams than an orange, has seen its vitamin content decrease by 22.7 per cent in just two decades. While the nutritional value of our foods has been declining since the 1940s, this decline has accelerated dramatically in the past 30 to 40 years, potentially affecting the conventional tastes of certain foods. 

The review focuses on two reasons for the possible decline in nutritional density — referred to as nutritional dilution in our diets: deficient soil biodiversity and fertility, and unbalanced, inadequate nutrition. 

Nutrient dilution has been primarily linked to the degradation of the soil in which crops are grown. Industrial farming practices — such as the use of synthetic fertilizers, pesticides, and herbicides to boost food production — along with the use of land solely for revenue generation, have caused significant damage to soil health.

The seeds have also been modified over the years. Through genetic engineering, the food industry has developed crops that have higher yields, grow faster, and resist pests and diseases, often at the expense of nutrient density. 

The food market also plays an important role in what landowners decide to produce. For example, in Argentina, soybean harvesting has expanded, as selling soybeans generates more revenue and carries less risk for farmers using genetically modified soybeans. 

Rising global temperatures caused by the climate crisis have also affected the quality of our foods. Sunlight can alter the chemical profile of soil, and increased solar radiation can raise soil temperatures. This accelerates the decomposition activities of typical soil microbes, leading to the faster breakdown of nutrients that would otherwise be preserved or decomposed more slowly. 

Additionally, higher levels of atmospheric carbon dioxide have been shown to affect the availability and quantity of nutrients — such as nitrogen, iron, and potassium in soil. Consequently, there is a decrease in nutrient uptake by crops, like rice and wheat. As a result, we consume food with reduced concentrations of proteins and essential minerals, which are crucial for metabolic functions such as tissue repair, immune health, and energy production. 

Our health lies in our daily habits and choices 

Nowadays, we consume more ultra-processed food, which is modified with a slew of artificial additives and preservatives to enhance taste, convenience, and durability. Even some loaves of bread found at the grocery store are considered highly processed due to the high amounts of salt, artificial colours, and sugars they contain. 

Having a diet based primarily on these types of foods can potentially lead to health issues. Now, don’t get me wrong — it is not about avoiding these foods completely. As long as we maintain a balanced diet, our bodies should be resilient enough to cope with the occasional surplus of trans fat we might consume when eating popcorn at the theatre or that decadent chocolate cake at our friend’s birthday party. 

But as scientific studies have shown, even foods once considered healthy — such as fruits and vegetables — fail to provide the same nutritional value they did 50 years ago. This raises the question: can we achieve a ‘balanced’ diet today? 

Overcoming obstacles to a healthy and balanced diet involves making better choices and being mindful of your budget when grocery shopping. While most Canadians — particularly students — continue to struggle with the cost of living and can’t easily afford the luxuries of organic produce, below is a list of actionable steps to achieve a balanced diet: 

  • Diversify your diet: keep a journal or take notes on your phone for a week or two to check what you have been eating. Once you have an overview of your diet, start making small changes. For example, replace refined grains with whole grains, and add more pieces of fruit or sides of vegetables. 
  • Consider supplementation: multivitamins are easily available at most grocery stores and can help you meet your daily recommendations for vitamins and minerals.
  • Go for local and fresh: grocery stores often indicate the origin of fruits and vegetables. The farther a food travels, the higher the chance it has been frozen for transportation. Local and fresh — not frozen — means less handling and storage, which results in better nutritional quality.
  • Switch grocery stores: looking for better prices can be daunting when you have a busy schedule, but buying produce boxes and freezing the items at home is an option. Getting together with friends to buy food in bulk is another alternative. 
  • Follow a season calendar: the prices and nutritional value of fruits and vegetables fluctuate with the seasons. Use a calendar to know when and what to buy. 

Many changes in the food industry are needed for our food to regain its nutritional value, and additional research is required to understand how this can be achieved. However, by focusing on dietary diversification, micronutrient supplementation, and improving the nutritional quality of our food choices, we can take meaningful steps to combat the effects of nutrient dilution in our modern food supply.