There is a familiar story about modern food. Healthy soil produces nutritious plants. Modern intensive agriculture has changed the soil and the way food is grown. But has this changed the nutritional quality of the food reaching our plates—and, if so, how?
Editor’s Overview
Researchers have reported historical differences in the concentrations of certain nutrients in some fruits, vegetables and grains. But identifying a difference is not necessarily the same as identifying its cause.
Could changes in soil quality be contributing? Could higher crop yields affect nutrient concentrations? Could the varieties we have bred for yield, appearance, firmness, transportability or shelf life have changed in other ways as well? Could environmental conditions also play a part?
And what about something much easier for ordinary people to notice—taste? Many people say that some fruits and vegetables no longer seem to have the flavour they remember. Is that simply nostalgia, or might something measurable have changed?
And ultimately, what—if anything—might these questions mean for our health?
These are the questions we will investigate. At HerballyOrganic, we do not need to decide the answer before examining the evidence.
Questions We Will Examine
As we work through the evidence, we will ask:
• What do we mean by healthy soil and soil depletion?
• Have concentrations of some nutrients in food changed over time?
• How reliable are comparisons between food grown decades apart?
• Could soil depletion contribute to any changes?
• Could crop breeding, increased yield, environmental conditions, growing practices and methodological differences also influence measured nutrient concentrations?
• When we select plants for desirable characteristics, could other characteristics change as well?
• Has flavour changed in some modern crops—and, if so, why might that matter?
• Could better-tasting fruits and vegetables encourage people to eat more of them?
• What do genetic engineering and gene editing add to this discussion?
• Does any of this demonstrate that modern diets are nutritionally inadequate?
• And does it provide evidence that an individual needs supplements?
We will return to these questions after examining the evidence.
1. Healthy Soil Is More Than Dirt
At first glance, soil can look like little more than the material that anchors a plant.
In reality, healthy soil is an extraordinarily complex living system containing minerals, organic matter, water, air, plant roots, fungi, bacteria and many other organisms.
The US Natural Resources Conservation Service describes soil health in terms of the continued capacity of soil to function as a living ecosystem that sustains plants, animals and humans.
In practical terms, healthy soil helps provide the physical, biological and nutritional environment in which plants can grow and obtain essential mineral nutrients.
But even the term soil depletion needs clarification.
It might refer to declining concentrations of particular minerals. It might involve loss of organic matter. Erosion can remove fertile topsoil. Compaction can interfere with root growth and water movement. Changes in pH, salinity, microbial communities and soil structure can also alter the environment in which plants grow.
So an important distinction appears immediately:
The amount of a mineral present in soil and the overall health of that soil are related—but they are not the same thing.
And that leads to our first question:
If the nutritional composition of a crop changes, can we assume that declining mineral content of the soil is responsible?
To investigate that, we first need to ask whether the composition of food itself appears to have changed.
2. Has the Nutritional Composition of Food Changed?
One frequently cited investigation was published in 2004 by Donald Davis and colleagues.
The researchers compared USDA food-composition data for 43 garden crops between 1950 and 1999. They examined 13 nutrients and reported statistically reliable group-level declines in six: protein, calcium, phosphorus, iron, riboflavin and vitamin C.
That is an observation worth taking seriously.
But what does it tell us?
It tells us that differences appeared in the recorded concentrations of certain nutrients across the two sets of USDA data.
It does not, by itself, tell us why those differences occurred.
The researchers considered several possible explanations and suggested that changes in cultivated varieties—including possible trade-offs between yield and nutrient concentration—could contribute to the observed pattern.
That immediately broadens our investigation.
Could the soil have changed?
Could the plants themselves have changed?
Could growing conditions have changed?
Could several influences be operating simultaneously?
Or could part of the apparent difference result from changes in sampling and measurement over nearly half a century?
And there is another important question. The Davis comparison ended in 1999. What has happened in the quarter-century since? Have nutrient concentrations continued to decline, stabilised, improved—or changed differently according to the crop, nutrient and growing environment?
More recent research gives us additional evidence to consider later in this article, particularly concerning changing atmospheric CO₂ and crop composition.
Before deciding what all this means, however, we need to ask how confidently foods grown many decades apart can actually be compared.
3. How Reliable Are Comparisons Across Many Decades?
Imagine comparing a carrot analysed in 1950 with a carrot analysed today.
Before concluding that any difference represents historical nutrient loss, we would need to know considerably more.
Were they the same variety?
Were they grown in similar soil?
Under comparable weather conditions?
Were they harvested at the same stage of maturity?
Were the edible portions sampled in the same way?
Were storage conditions comparable?
And were the laboratory techniques equally accurate?
These aren’t trivial questions.
A critical review by Robin Marles examined historical reports of declining mineral concentrations and highlighted problems including differences in crop varieties, geographical origins, maturity, sampling and analytical methods.
The review therefore urged caution in interpreting historical food-composition tables as straightforward evidence of widespread nutrient decline.
This does not mean historical differences should be dismissed.
It means that:
A measured difference and an explanation for that difference are two separate questions.
Could we find evidence that avoids some of the limitations of comparing old food tables with modern ones?
Fortunately, an extraordinary long-term agricultural experiment allows us to investigate that question in a different way.
4. What Can 160 Years of Wheat Tell Us?
The Broadbalk Wheat Experiment at Rothamsted in England began in 1843 and has continued for generations.
Its particular value for our question is that researchers have access to archived wheat grain and soil samples collected across many decades.
Instead of relying only on comparisons between historical and modern food-composition tables, scientists can analyse actual material preserved from different periods.
What did they find?
Concentrations of zinc, iron, copper and magnesium in wheat grain remained relatively stable from 1845 until the mid-1960s. From then onward, a significant decline in these concentrations became evident.
At first glance, that might appear to support a simple soil-depletion explanation.
But then the researchers examined the soil.
Concentrations of those minerals in the soil had remained stable or increased.
The decline in grain mineral concentration occurred around the period when semi-dwarf, higher-yielding wheat cultivars were introduced. The researchers’ analysis identified increasing yield and harvest index as significant factors associated with the downward trend in grain mineral concentrations.
This experiment cannot tell us what happened to every crop in every soil.
Nor does it establish that soil degradation is unimportant.
But it gives us an important clue:
A decline in mineral concentration within a crop does not necessarily mean that the corresponding minerals have declined in the soil.
So what else might be happening?
5. Could Greater Yield Affect Nutrient Concentration?
Imagine two plants.
One produces a certain quantity of grain.
Another has been selected to produce substantially more.
If the second plant produces more carbohydrate or edible material without a proportional increase in the amount of a particular mineral incorporated into that material, the mineral concentration per unit of food could become lower.
This is commonly described as a dilution effect.
Evidence from the Broadbalk wheat experiment is consistent with such an effect for several minerals.
But here we need to avoid turning one possible explanation into another universal conclusion.
Different crops may respond differently.
Different nutrients may behave differently.
Growing conditions may alter the relationship.
And higher yield itself can arise through different biological mechanisms.
So the evidence raises a possibility rather than giving us a rule that applies to every food:
Increasing agricultural productivity may sometimes be accompanied by changes in the concentration of particular nutrients.
And this raises another question that nutrient tables alone cannot answer:
While we were selecting crops to produce more, did anything else change?
6. Has Something Else Changed—What About Taste?
Numbers in a laboratory report are not the only way people experience food.
There is another observation often heard around kitchen tables, gardens and greengrocers:
“Fruit and vegetables don’t seem to taste the way they used to.”
Some people describe tomatoes as bland. Others say strawberries look beautiful but have little flavour. Some describe modern fruit and vegetables as watery compared with what they remember.
Is this simply nostalgia?
Or might something measurable have changed?
Taste is much more complicated than the concentration of a single nutrient. What we experience as flavour can reflect sugars, acids, aromatic compounds, texture, water content and ripeness, together with interactions among them.
Variety, soil and growing conditions, maturity at harvest, refrigeration, storage and transportation may all influence the final eating experience.
Tomatoes provide an especially interesting example.
A major 2017 study examined 398 modern, heirloom and wild tomato varieties and investigated the chemistry and genetics underlying flavour. Researchers identified flavour-associated compounds that were less abundant in many modern commercial varieties and genetic variants associated with desirable flavour that had become less common during domestication and crop improvement.
This does not establish that every modern tomato tastes worse.
And it certainly does not establish that every modern fruit or vegetable has lost flavour.
But it does give us evidence that, at least in some crops, measurable characteristics associated with flavour have changed.
That leads naturally to another question:
Why might those characteristics have changed—and could they have changed while we were pursuing other desirable qualities in our food crops?
7. What Did We Gain—and Did Anything Else Change?
For generations, farmers and plant breeders have selected crops for useful characteristics.
Higher yield. Disease resistance. More uniform size and appearance. Firmness. Predictable ripening. Resistance to damage. Longer storage. Ability to withstand transportation.
These characteristics can provide genuine advantages.
A tomato that survives transportation without turning to pulp has obvious practical value. A crop resistant to disease may reduce losses. A higher-yielding crop may produce more food from the same area of land.
But living organisms are interconnected biological systems.
When we select strongly for one characteristic, an important question follows:
Could something else change at the same time?
The tomato research gives us a concrete reason to ask.
In some modern varieties, improvements pursued during breeding occurred alongside reductions in some flavour-associated compounds and genetic variants.
This does not prove that one particular breeding objective directly caused every flavour change. But it demonstrates why the wider question matters.
And it gives us four questions that can become part of the HerballyOrganic Compass:
What did we gain?
What did we lose?
What else changed?
How do we know?
Notice that these questions contain no predetermined conclusion.
Sometimes the evidence may reveal an important benefit with little detectable disadvantage.
Sometimes it may reveal a trade-off.
Sometimes both benefit and disadvantage may occur.
And sometimes the evidence may simply be insufficient to know.
8. Could Better Taste Help Us Eat Better?
This brings us to a question that is easily overlooked in discussions of nutrition.
Health advice frequently encourages people to eat more fruits and vegetables.
But perhaps we should also ask:
What makes people actually want to eat them?
Taste and sensory enjoyment are among the influences on food choice, although they are certainly not the only ones. Cost, availability, habit, culture, convenience and familiarity can all matter.
This suggests a question worth investigating:
If fruits and vegetables taste better, might people be more inclined to choose and eat them regularly?
If so, flavour could have health significance that extends beyond pleasure.
But we need to be careful with the chain of reasoning.
We should not jump from:
better flavour → more vegetables → lower cholesterol → prevention of cardiovascular disease.
There are too many steps and too many other influences for that sequence to be assumed.
A more useful question is:
Could improving the flavour and enjoyment of nutritious whole foods help make healthier dietary patterns easier to maintain over time?
Fruits and vegetables can contribute fibre, potassium, vitamins, minerals and a wide range of plant compounds to the diet. Eating them may also replace some foods with a less favourable nutritional profile.
So perhaps the practical nutritional value of food involves more than simply what laboratory analysis says it contains.
There is also the question of whether people want to eat it.
The nutritional value of a healthy food has limited practical benefit if people consistently don’t want to eat it.
That observation does not settle the science.
It gives us another question worth pursuing.
9. Where Does Soil Fit Into This Larger Picture?
We can now return to the subject in our title.
Could soil depletion affect modern nutrition?
There are sound biological reasons to investigate the possibility.
Plants depend upon their growing environment for mineral nutrients. Soil structure, chemistry, organic matter, water availability and biological activity may influence nutrient availability, root development and plant health.
But the evidence we have examined suggests that several different questions need to be distinguished.
How much of a nutrient exists in the soil?
How much of it is available to the plant?
How efficiently does the plant absorb it?
Where does the plant allocate it?
How much edible material does the plant produce?
What concentration appears in the portion we eat?
And now we can add:
How does the finished food taste—and could that affect whether people choose to eat it?
These questions are related.
They are not interchangeable.
So perhaps the investigation should not be limited to:
Is soil depletion responsible?
A broader question is:
How might soil, plant genetics, agricultural practices, yield and environmental conditions interact to influence the food that eventually reaches our plate?
That is a more complicated question.
It may also be a more useful one.
10. Could the Atmosphere Affect Nutrient Concentration Too?
There is another influence that illustrates just how interconnected this system can be.
Plants use carbon dioxide during photosynthesis.
Could increasing atmospheric CO₂ affect the nutritional composition of plants?
Research suggests that it can under some conditions.
A large 2014 meta-analysis by Irakli Loladze examined 7,761 observations across 130 species and cultivars. Under elevated CO₂, the overall concentration of minerals in C3 plants was reduced by an average of about 8%. C3 plants include important food crops such as wheat and rice.
More recent research has continued to investigate this question. A 2025 meta-analysis brought together 5,324 data entries representing 29,524 observation pairs across 43 crops and 32 nutrients and antinutrients. Its findings add to evidence that elevated CO₂ can alter the nutritional composition of edible plant tissues—but not in one simple, uniform direction for every nutrient and every crop.
A 2026 scoping review of experimental studies, meta-analyses and modelling research published through 2024 likewise found a more complicated picture. Some nutritional components increased under particular climate-related exposures, while declines were reported for a number of essential minerals, folate and dietary fibre.
This newer evidence is important because it helps answer the question we raised earlier:
Have nutrient concentrations simply continued to decline since 1999?
The evidence does not justify such a simple conclusion.
Instead, it suggests that crop composition can continue to change in response to environmental conditions, and that the direction and magnitude of those changes may depend upon the crop, nutrient and conditions being studied.
This gives us another important clue:
Changes in the nutritional composition of a plant can occur even when depletion of minerals in the soil is not the proposed cause.
Our picture is becoming broader again.
Soil may matter.
Plant genetics may matter.
Yield may matter.
Agricultural practices may matter.
Atmospheric conditions may matter.
And the interactions among them may matter.
11. What About Traditional Breeding, Genetic Engineering and Gene Editing?
Human beings have altered crops for thousands of years.
Traditional selection and breeding work with inherited genetic variation, selecting and combining desirable characteristics through reproduction among compatible plants.
Other methods have also been used. During the twentieth century, for example, plant breeders deliberately induced mutations using radiation or chemicals and then selected plants displaying useful characteristics.
Modern genetic engineering can introduce or modify genetic material in ways that differ from conventional crossing.
Newer gene-editing methods can make targeted changes to particular DNA sequences, sometimes without leaving foreign DNA in the resulting plant.
These methods are not identical.
So simply labelling something “modified” tells us relatively little about its nutritional consequences.
The more useful questions remain:
What was changed?
Why was it changed?
What benefit was sought?
Did anything else change?
How was that investigated?
In Australia and New Zealand, Food Standards Australia New Zealand (FSANZ) assesses GM foods case by case. Its assessments consider intended and unintended effects, including compositional changes that could have nutritional or safety significance, and compare the modified food with an appropriate conventional counterpart.
This brings us to an important distinction.
Suppose a plant is modified to change characteristic A.
Testing then finds that characteristic B has also changed slightly, even though B was not the intended target.
The discovery of that second change does not, by itself, tell us whether it is beneficial, harmful or of little practical significance.
Its significance still has to be investigated.
Conversely, if testing does not identify harm, that does not necessarily demonstrate that nothing else whatsoever changed. It tells us what the investigation was able to detect within the questions, methods and limits of that assessment.
So the more useful questions are:
What changed? Does the change matter? And how thoroughly has it been investigated?
This approach leaves room for evidence without requiring either automatic acceptance or automatic rejection of a technology.
12. Can Human Intervention Improve Nutritional Value Too?
Fairness requires us to examine the question from the other direction.
If human intervention can sometimes alter food in undesirable ways, can it also improve its nutritional value?
Plant breeding and agricultural practices can be used deliberately to increase the concentration or availability of particular nutrients in food crops—a process broadly described as biofortification.
Different approaches may be used, including conventional plant breeding, agronomic practices and, in some circumstances, modern biotechnology.
This is important because it prevents us from adopting another overly simple rule:
Natural = good. Human intervention = bad.
But the opposite rule would be equally unjustified:
New technology = improvement.
Instead, each intervention brings us back to the same questions:
What did we gain?
What did we lose?
What else changed?
How do we know?
Sometimes an intervention may improve a characteristic we value without evidence of an important disadvantage.
Sometimes there may be a trade-off.
Sometimes another characteristic may change unexpectedly.
And sometimes the evidence may remain incomplete.
The important point is that the method used to change a crop does not, by itself, tell us whether the nutritional result is better, worse or essentially unchanged.
That has to be investigated.
13. What About Organic Food?
The word organic frequently enters discussions about soil and food quality.
People may choose organically produced food for a variety of reasons, including farming practices, environmental considerations, pesticide exposure, personal values, taste or perceptions about food quality.
But for our present investigation, the nutritional question is narrower:
Does an organic label itself tell us how nutrient-dense a particular food will be?
Not necessarily.
Crop variety, soil conditions, climate, growing practices, maturity at harvest, storage and other factors may all influence the composition of the food we eventually eat.
Organic farming methods may influence aspects of soil health, but the label alone cannot tell us the concentration of every nutrient in a particular carrot, apple or tomato.
The same caution applies to taste.
A locally grown tomato allowed to ripen more fully and selected for flavour may provide a very different eating experience from a variety selected primarily for firmness and long-distance transport. But the word organic alone does not tell us whether that will be the case.
So again, a label gives us useful information—but not the complete answer.
How was the food grown? What variety is it? What condition was the soil in? When was it harvested? How was it stored and transported? And what was actually measured?
These questions may tell us considerably more about a particular food than assuming that either organic or conventional automatically settles the nutritional question.
A label can tell us something about how food was produced without telling us everything about the food itself.
14. Has Modern Food Become Nutritionally “Empty”?
We can now return to one of the stronger claims sometimes made about modern food:
Has intensive agriculture left our food nutritionally “empty”?
The evidence we have examined does not support such a sweeping conclusion.
Historical comparisons have reported declines in the concentrations of some nutrients in some crops. Long-term wheat research has also documented declines in several minerals—but importantly, those changes occurred even though the corresponding mineral concentrations in the soil remained stable or increased.
Research into crop breeding, yield and elevated atmospheric CO₂ gives us further reasons to think that the nutritional composition of food can change for more than one reason.
At the same time, none of this means that soil degradation is irrelevant, or that nothing important has changed in modern agriculture.
The more defensible conclusion is more nuanced:
Some characteristics of some foods appear to have changed over time. The size, causes and nutritional significance of those changes vary according to the crop, nutrient, growing environment and evidence being examined.
That is quite different from saying that modern food contains no meaningful nutrition.
It also prevents us from making the opposite mistake—assuming that because modern food remains nutritious, questions about soil, crop composition, flavour and agricultural change no longer matter.
The evidence allows neither extreme.
Modern fruits, vegetables and grains remain important sources of nutrients. But understanding how their composition may be changing—and why—remains a legitimate scientific question.
And that brings us to a more personal question:
Could these issues become more important as we grow older?
15. Does Any of This Matter More as We Grow Older?
If the concentration of a particular nutrient in a food changes, it is tempting to assume that the person eating that food must therefore receive less of that nutrient.
But human nutrition is not quite that simple.
Our nutritional status depends upon the whole picture—what foods we eat, how much we eat, how varied our diet is, how nutrients are absorbed and used, our individual requirements, health conditions, and sometimes the medicines we take.
Some of these factors can become particularly relevant with age.
Changes in appetite, food intake, digestion, absorption, oral health and medication use can all influence nutritional status in older adults. But they do not affect everyone in the same way or to the same degree.
This gives us an important distinction:
A change in the average nutrient concentration of a crop is not a diagnosis of nutritional deficiency in the person eating it.
Nor does evidence of a possible nutritional gap automatically tell us what an individual needs.
To understand that, we have to move from the composition of the food to what happens when the person actually eats it.
And What Happens After the Food Reaches Our Plate?
Even knowing exactly what a food contains would not tell us exactly what the body ultimately obtains from it.
Digestion begins with the physical processing of food in the mouth. Chewing breaks food into smaller pieces and mixes it with saliva, changing the physical structure presented to the digestive system.
That raises another interesting question:
Could how well we chew influence how accessible some nutrients become?
Research suggests that mastication can influence the release and bioaccessibility of some nutrients and plant compounds—that is, how much becomes available for absorption during digestion.
But we should not take that observation further than the evidence allows. The size and practical importance of the effect vary according to the food and nutrient being studied, and it has not been established that simply chewing longer produces a large nutritional benefit across all foods.
Oral health may matter as well. In older adults, poorer chewing ability and dentition have been associated with differences in food choice and nutrient intake, although chewing is only one part of a much larger nutritional picture.
This gives us another useful question to place beside the question we started with:
It is not only “What nutrients are in my food?” but also “How effectively can my body make those nutrients available and use them?”
And that distinction becomes especially important before we make the next leap:
If modern food may have changed, does that mean we need supplements?
16. Does Concern About Modern Food Mean We Need Supplements?
This is where a legitimate scientific question can easily become a marketing message.
The reasoning may sound something like this:
Modern soils are depleted → modern food is nutrient-poor → therefore everyone needs supplements.
But the evidence we have examined does not support that chain of reasoning.
We have seen that changes in the nutrient concentration of some crops have been reported. We have also seen that soil mineral depletion is not necessarily the cause. Crop variety, yield, agricultural practices, environmental conditions and other factors may all contribute.
More importantly, even if the concentration of a particular nutrient in a particular food has declined, that does not tell us whether an individual consuming a varied diet is deficient in that nutrient.
A supplement may be useful when there is a clear nutritional purpose—for example, when dietary intake is inadequate, absorption is impaired, requirements are increased, a deficiency has been identified, or there is another evidence-based reason for supplementation.
But that is very different from assuming that everyone requires supplements because modern agriculture has changed.
The HerballyOrganic approach is therefore:
Notice → Ask → Investigate → Understand → Act → Review
Notice the concern.
Ask the right question.
Investigate the evidence.
Understand what it does—and does not—tell us.
Act when there is a sound reason to act.
And review the decision as circumstances or evidence change.
A possible nutritional gap is not the same as a proven deficiency.
And a concern about modern food is not, by itself, evidence that a supplement is needed.
The more useful question is:
What does the evidence suggest about this person’s nutritional needs—and what is the most appropriate way to meet them?
Sometimes the answer may involve food.
Sometimes it may involve addressing an underlying health or absorption problem.
Sometimes a supplement may have a legitimate role.
And sometimes no additional intervention may be necessary.
The decision should follow the evidence—not the marketing story.
17. What Does the Evidence Allow Us to Conclude?
We began with a simple question:
Could soil depletion affect modern nutrition?
The evidence suggests that soil quality can influence the environment in which plants grow and the availability of nutrients to them. Degraded soil therefore deserves serious attention.
But the evidence does not support reducing the nutritional story of modern food to soil depletion alone.
Historical food-composition data suggest that concentrations of some nutrients in some crops have changed over time. Yet comparisons across many decades contain important uncertainties, including differences in crop varieties, growing conditions, sampling and analytical methods.
Long-term wheat research provides particularly valuable evidence. It found declines in several grain minerals even though concentrations of those minerals in the soil remained stable or increased. Higher yields and changes in cultivated varieties appear to be important parts of that story.
Research into tomatoes gives us another piece of the picture: some flavour-associated compounds and genetic variants have become less abundant in many modern commercial varieties. This shows that when crops are selected for desirable characteristics, other characteristics can change too.
Environmental conditions add another layer. Research into elevated atmospheric CO₂ indicates that plant composition can change even when declining soil mineral concentrations are not the proposed explanation.
Modern agricultural and plant-breeding practices have also delivered genuine benefits—including greater productivity, disease resistance, improved storage and transport characteristics, and the possibility of deliberately improving the nutritional characteristics of some crops.
So what can we reasonably say?
Some characteristics of some foods have changed.
Those changes do not have one universal cause.
Soil may be part of the explanation in some circumstances, but it is not the whole explanation.
Changes in crop composition do not demonstrate that modern food is nutritionally “empty.”
Nor do they demonstrate that everyone eating modern food needs supplements.
And several questions remain open—including how these influences interact across different crops, environments and agricultural systems, and what their long-term nutritional significance may be for different populations.
That uncertainty is not a weakness in the investigation.
It is part of the evidence.
Conclusion: From a Simple Story to a More Complete Picture
We began with a familiar story:
Healthy soil produces nutritious food. Modern agriculture has depleted the soil. Therefore modern food contains fewer nutrients.
There are elements of truth within that story—but the evidence reveals a much more complicated picture.
Soil matters. But so do plant genetics, crop variety, yield, agricultural practices, environmental conditions, maturity at harvest, storage and the way food eventually reaches our plate.
We have also seen that nutritional composition is only part of the story. Characteristics such as flavour can change as crops are selected for other desirable qualities, and those changes may influence how people experience and choose food.
Human intervention is not inherently beneficial or harmful. It can produce advantages, disadvantages, trade-offs—or changes whose significance is still uncertain.
That is why four simple questions have repeatedly guided this investigation:
What did we gain?
What did we lose?
What else changed?
How do we know?
These questions apply far beyond soil and agriculture.
They remind us that noticing a change is not the same as identifying its cause, and identifying a possible nutritional concern is not the same as demonstrating a deficiency or establishing the need for a supplement.
Perhaps the most useful lesson from this investigation is therefore not a single claim about modern food.
It is a way of examining claims about health.
Begin with the question. Examine the evidence. Consider alternative explanations. Recognise uncertainty. Then allow the conclusion to follow.
That is the approach we aim to follow at HerballyOrganic.
Not because every question will produce a simple answer—but because our health decisions deserve something better than a simple story when the evidence tells us the picture is more complex.
Evidence Rating Summary
The evidence examined in this article does not carry equal weight. The following ratings reflect the strength and consistency of the evidence for the specific statements shown—not a rating of an entire subject.
🟢 Well Supported — Soil is a complex living system whose physical, chemical and biological characteristics influence plant growth and nutrient availability.
This is well established in soil science.
🟢 Well Supported — The concentrations of some nutrients in some crops have changed over time.
Historical food-composition studies and long-term agricultural experiments provide evidence of changes in particular nutrients and crops. This does not mean that every nutrient in every food has declined.
🟢 Well Supported — Crop genetics and yield can influence nutrient concentration.
Long-term wheat evidence and other crop research show that changes in cultivated varieties and increased yield can affect the concentration of particular nutrients in edible plant tissues.
🟢 Well Supported — Elevated atmospheric CO₂ can alter the nutritional composition of some crops.
Experimental studies and large evidence syntheses show changes in mineral and other nutritional components under elevated CO₂, although the size and direction of effects vary among crops and nutrients.
🟢 Well Supported — Breeding can alter characteristics other than those most visibly selected for.
Research in crops such as tomatoes demonstrates measurable changes in flavour-associated compounds and genetic variants during domestication and crop improvement.
🟡 Supported, but Qualified — Soil degradation can contribute to changes affecting crop nutrition.
Soil condition can influence nutrient availability and plant growth, but a measured decline in the nutrient concentration of a crop cannot automatically be attributed to depletion of that nutrient in the soil.
🟡 Supported, but Qualified — Chewing can influence the accessibility of some nutrients and plant compounds.
Mastication changes food structure and can affect nutrient release and bioaccessibility, but the magnitude and practical nutritional importance vary considerably among foods and nutrients.
🟠 Uncertain / Still Developing — Better-tasting fruits and vegetables may help people maintain healthier dietary patterns.
Taste influences food choice, but many other factors—including cost, availability, culture, habit and convenience—also affect what people eat. The complete pathway from improved flavour to long-term health outcomes should not be assumed.
🔴 Not Supported by the Evidence Examined Here — Modern food is nutritionally “empty,” or everyone needs supplements because modern soils are depleted.
The evidence examined in this article does not establish either claim. Individual nutritional needs require a much broader assessment than a general claim about modern agriculture.
Evidence ratings are not permanent verdicts. They describe what the available evidence allows us to say at the time of review and should change when stronger evidence changes the picture.
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