Is Your Food Less Nutritious Than It Used to Be?

Social media has a new anxiety for you, delivered fresh alongside your morning doomscroll: the food you're eating is nutritionally hollow compared to what your grandparents ate, thanks to degraded soil and industrial farming. The broccoli you bought at the store? Basically a green water balloon. Your spinach? Decorative. Better add seventeen supplements to fix what Big Agriculture broke.

So, is your food less nutritious than it used to be? And should you totally freak out and buy a bunch of supplements before resigning yourself to shop at Erewhon forever, lest you give in and contract beriberi?

The actual story is more interesting than either the catastrophists or the dismissers want to admit. (We take a deep dive into the related topic of organic food in this episode of Your Diet Sucks.)

Has the nutrient content of vegetables really declined?

There is some research on nutrient decline in produce. It's not a conspiracy theory, and it's not nothing. In 2004, researcher Donald Davis and colleagues published a landmark study in the Journal of the American College of Nutrition examining USDA nutritional data for 43 vegetables and fruits, comparing figures from 1950 to 1999. They found statistically significant declines in six nutrients across that time period: protein, calcium, phosphorus, iron, riboflavin, and vitamin C. The median declines ranged from about 6 percent for protein to 38 percent for riboflavin (Davis et al., 2004). A similar analysis of British food composition data from 1930 to 1980 found average declines in calcium, iron, and potassium in vegetables (Mayer, 1997). These findings have been corroborated in more recent work, including a field experiment showing approximately a 5 percent reduction in micronutrients in crops grown under elevated CO2 conditions (Ziska et al., 2012).

Those are real numbers. So what's causing them?

Why is food less nutritious? Blame breeding, not soil

The wellness-content version of this story blames depleted soil and industrial farming. Modern farming and modern soil are bad, because modernity is bad, and any fruit or vegetable it produces will also be bad.

But the actual science points to something more specific and arguably more interesting: selective breeding. When agricultural researchers spent decades optimizing crops for yield, size, pest resistance, and shelf life, they created what researchers call the "dilution effect." A bigger broccoli floret contains more water and carbohydrates, but the concentration of vitamins and minerals in that larger structure doesn't keep pace with the growth. The nutrient density gets diluted by volume. Davis described this as a "genetic dilution effect" distinct from soil depletion, representing a trade-off built directly into the genetics of modern crop varieties.

Does soil depletion actually make food less nutritious?

The soil-depletion narrative, which dominates the social media version of this story, is actually the weaker part of the evidence. As researchers at the University of Wisconsin noted in a detailed reexamination of the data, the widespread use of soil testing and fertilizers in modern agriculture argues against widespread mineral depletion as the primary driver (Barak, 2000). A Frontiers in Sustainable Food Systems review put it plainly: when it comes to translating soil health metrics into actual nutritional differences in crops, the robust evidence is not yet there (Montgomery et al., 2021). That doesn't mean soil health is irrelevant, and it doesn't mean industrial monoculture has no downsides. It means the causal pathway being sold to you on Instagram is oversimplified.

How rising CO2 changes the nutrients in crops

There's also a genuine climate angle that gets less attention, because addressing it might require policy change rather than buying some discounted supplements at the link in bio. As atmospheric CO2 rises, crops grow faster and accumulate more carbohydrates. The result is that protein, iron, and zinc concentrations in staple crops like wheat and rice are declining relative to historical baselines, and field experiments confirm this effect (Myers et al., 2014). This is a real, detectable mechanism, separate from farming practices, and it operates at a global level that will matter especially for food-insecure populations.

Do you need supplements because vegetables are less nutritious?

So: is your food less nutritious than it was seventy years ago? Probably somewhat, in specific micronutrients, primarily because we bred crops to be large and productive rather than dense.

Is your kale a nutritional wasteland that requires pharmaceutical intervention?

Absolutely not.

The same researcher who identified these declines, Davis himself, was clear that this finding doesn't mean people should avoid fruits and vegetables. It means we should eat more of them, eat a wider variety, and pay attention to what we're optimizing in our food systems. The takeaway from the research isn't "buy supplements." It's "eat the broccoli anyway, and maybe more of it."

Notice where that concern actually lands: populations who get most of their calories and micronutrients from one or two staple grains, where a few percent shift in zinc or iron is an epidemiological problem at scale. That's a population-and-policy issue, not a "your kale is letting you down" issue. For an individual in a food-secure setting eating varied produce, the effect is swamped by everything else: how much produce you eat, variety, whether you eat it at all, and cooking and storage losses, which dwarf these differences. The nutrition researchers who study this all come back to the same place: this isn't a 50 percent collapse in nutrient density, so a person eating a range of different-colored fruits and vegetables will still meet their needs. And many point out that the increase in food availability and affordability far outweighs nutrient dilution as a net good for the world.

Huh, funny that the folks loudest about this narrative online seem more intent on selling a supplement or fear-mongering than advocating for food access or policy? Weird. It's almost like their use of this narrative is a cynical attempt to monetize fear rather than to ensure that the world is getting enough vitamin C. Could just be me.

The wellness industry does something predictable with findings like these: it takes a real but modest signal, inflates it to catastrophic proportions, and positions a product as the antidote. Soil depletion content is almost always a highway toward a supplement pitch, a "nutrient-dense" branded food, or a detox protocol. The actual scientists studying this question are careful to contextualize their findings. The influencers are not.

Eating a varied diet with abundant fruits and vegetables remains the most evidence-supported nutritional strategy, full stop. The documented declines in riboflavin and vitamin C in some crops are not so dramatic that they offset the profound benefits of eating produce over not eating produce. Where this research is genuinely useful is in the macro conversation about food policy: what we optimize for when we breed crops, how we structure agricultural incentives, and what happens to global nutrition as CO2 continues to rise. These are real concerns. They just don't require you to spend a hundred dollars on a greens powder.

Your carrots are less nutritious than your grandmother's carrots. Eat more carrots.

The bottom line: is food less nutritious today?

Some nutrients in fruits and vegetables have declined modestly since the mid-20th century, primarily due to selective breeding that prioritized yield over nutrient density. The soil-depletion story popular on social media overstates what the evidence supports. Rising atmospheric CO2 is a separate and real driver of micronutrient dilution in staple crops. None of this justifies panic, supplement purchases, or abandoning produce. It's an argument for eating a varied, plant-forward diet and for taking agricultural policy seriously. The scientists who found these declines were explicit: eat more vegetables, not fewer.

If the "your food is empty" content keeps landing in your feed and you want somewhere to check it against actual humans, the weekly nutrition question thread on the YDS Patreon is where Kylee takes those apart, alongside the monthly bonus episodes and a community that is refreshingly uninterested in selling you a greens powder.

References

Barak, P. (2000). Soil health and nutrient depletion: Reexamining USDA food composition data. University of Wisconsin Soil and Environmental Sciences.

Davis, D. R., Epp, M. D., & Riordan, H. D. (2004). Changes in USDA food composition data for 43 garden crops, 1950 to 1999. Journal of the American College of Nutrition, 23(6), 669–682. https://doi.org/10.1080/07315724.2004.10719409

Mayer, A. M. (1997). Historical changes in the mineral content of fruits and vegetables. British Food Journal, 99(6), 207–211. https://doi.org/10.1108/00070709710181540

Montgomery, D. R., Bikle, A., Archuleta, R., Brown, P., & Jordan, J. (2021). Soil health and nutrient density: Beyond organic vs. conventional farming. Frontiers in Sustainable Food Systems, 5, 699147. https://doi.org/10.3389/fsufs.2021.699147

Myers, S. S., Zanobetti, A., Kloog, I., Huybers, P., Leakey, A. D. B., Bloom, A. J., Carlisle, E., Dietterich, L. H., Fitzgerald, G., Hasegawa, T., Holbrook, N. M., Nelson, R. L., Ottman, M. J., Raboy, V., Sakai, H., Sartor, K. A., Schwartz, J., Seneweera, S., Tausz, M., & Usui, Y. (2014). Increasing CO₂ threatens human nutrition. Nature, 510, 139–142. https://doi.org/10.1038/nature13179

Ziska, L. H., Bunce, J. A., Shimono, H., Gealy, D. R., Baker, J. T., Newton, P. C. D., Reynolds, M. P., Jagadish, K. S. V., Zhu, C., Howden, M., & Hays, D. (2012). Food security and climate change: On the potential to adapt global crop production by active selection to rising atmospheric carbon dioxide. Proceedings of the Royal Society B, 279(1745). https://doi.org/10.1098/rspb.2012.1005