Is organic food actually healthier?

Luke Tulloch

I can already tell this one will be controversial. It’ll elicit eye-rolls from some and vehement proclamations from others. I’m going to take a scientific look at whether organic foods are actually healthier or safer than conventional produce but as always, I’m going to leave the moral arguments at the door.

I need to briefly address a few things first, though. Painting every crop with the same brush conveniently avoids a lot of nuance. Farming practices can be vastly different between regions and crop types, and it’d be beyond me to try and address industry regulations across the world, which means that trying to simply compare organic versus non-organic is like comparing organic apples and non-organic oranges (Sorry, awful pun).

What I’ll attempt to do instead is give a concise view of what the body of scientific literature says as a whole. I should also mention at the outset that I don’t intend on creating a false dichotomy here – you can certainly eat a mix of organic and non-organic foods but at the risk of overstating “it depends”, I’ll try and just keep the comparisons straightforward.

Before we get into it, you need to be familiar with the concept of heterogeneity. Heterogenous means diverse, varied, mixed.

Ideally, we want reasonably low heterogeneity in the overall body of literature. In other words, if every study used a different method of testing, a different study design, a different group of foods collected at different times of the year from different regions – well, it makes it really hard to compare apples with apples.

For research to be most effective, it needs to be replicated. This validates prior research and bolsters the pool of available data, but only if the studies being performed use similar enough methods to produce reliable data.

Keep this in mind as you read on because it’s a big problem in trying to answer whether organic food is really better for you.

Why is organic food ‘better’ for you?

Generally, organic certification requirements require that organic foods are grown without synthetic pesticides fertilizers, and with minimal use of hormones and antibiotics. In addition, it’s usually stipulated that organic crops are not genetically modified and have minimal food additives to prolong shelf life and enhance colour or flavour.

Organic livestock is usually fed with organically grown crops and often comes with the assurance of free-range conditions: access to fresh air, direct sunlight and plenty of space outside.

In addition to environmental concerns (which are being set aside for the purposes of this article), consumers tend to view organic foods as both healthier and tastier than conventionally produced alternatives.

There are two separate questions we should try and answer.

1. Is the nutritional value of organic foods higher than non-organic?
2. Is the level of pesticides lower in organic or non-organic?

The subtext to each of these is whether organic food is worth the extra cost, so we can make a pragmatic decision about what suits our own household.

Organic vs Non-Organic Nutrients

The nutritional value of food is highly contextual. We need a variety of foods to satisfy macro- and micronutrient requirements. No single food can provide the necessary vitamins and minerals for optimal health, and the nutrient matrix within whole foods can include many compounds capable of affecting health. These include antioxidants, polyphenols, fatty acids, fibre, vitamins and minerals.

I’ve argued before that variety is key to health. The highest quality, most nutrient dense spinach on the planet doesn’t keep adding to your health beyond a certain point, and you’re still likely to be in a decidedly unhealthy state if that’s all you eat.

This makes judging the nutritional value of foods a bit difficult, but several studies have compared the differences between organic and non-organic foods. One of the problems with these analyses is that statistical and practical significance is sometimes overlooked – does it really matter if you get 5% more vitamin C from an organic orange? Is that something that will meaningfully impact your health?

Further, we don’t yet understand the full impact of various compounds like polyphenols and antioxidants on our health. While we might assume that they’re broadly beneficial, we don’t have an objective way of quantifying it.

One review of the scientific literature looked at levels of the following commonly studied nutrients:

Only one nutrient (phosphorous) was found to be consistently higher in organic produce. The authors note that “it is unlikely to be clinically significant because near-total starvation is needed to produce dietary phosphorus deficiency”, which is why you’ve probably never heard of anyone telling you to increase your phosphorous intake.

Importantly, some studies definitely did find that nutrient concentrations were higher in organic foods. For example, omega 3 fatty acids were found to be higher in organic dairy and chicken in some studies. There are both sides of the coin to consider though, and other studies found that conventionally grown foods were more nutrient dense.

In summary, the current body of evidence is not hugely convincing one way or another. For some foods or nutrients there are simply not enough studies available to make a solid claim, while for others the way the studies were set up means there is not enough data synthesized from similar methods to be conclusive (this is referred to as heterogeneity – study setups and results are all over the place).

I think it’s important to reiterate that even the same crop type grown in the same location can have wildly different nutrient concentrations. To work out the average and compare it between organic and non-organic foods means quite a lot of data has to be collected.

For example, the season of sampling and the brand of milk are important determinants of nutrient and fatty acid levels because organic and conventional cows may have similar diets in the winter but different diets in the summer when grass is available for organic cows.

So, the answer to our first question:

Q: Is the nutritional value of organic foods higher than non-organic?

A: Sometimes yes, sometimes no. On average there’s no compelling evidence to suggest there is any difference.

Do organic foods have less pesticides?

On to our second question. This one has potential implications for the environment (I won’t explore this in depth, but some food for thought here: some natural pesticides can have the same potential for adverse health and environmental effects as synthetic ones), but we also need to look at whether we’re getting more pesticide residue on the food we bring into our homes and whether this is harmful to our health.

Here’s where organic foods seem to have the edge. Conventional produce was found to have 30% higher risk of pesticide contamination than organic produce in this systematic review. This needn’t set alarm bells ringing, though. Despite the higher levels of pesticide residue, the conventionally grown produce was still well within safety limits. We are exposed to toxic by-products everywhere in our daily lives (cleaning products, exhaust fumes, naturally occurring toxins in plant foods etc) but as the saying goes “the dose maketh the poison”.

The answer to our second question, then:

Is the level of pesticides lower in organic or non-organic?

It’s lower on average in organic foods, but that might not make any measurable health impact.

Can you wash off pesticides?

It’s also possible to reduce risk of contamination by thoroughly washing fruits and vegetables. The National Pesticide Information Center in the US recommends eating a variety of foods to minimise exposure to any single pesticide, and thoroughly washing your produce under running water to reduce pesticide levels.

One study compared the effectiveness of three different washing methods at removing two common pesticides from apples. Of the three solutions used (tap water, a 1% baking soda + water mixture and a Clorox bleach solution) the baking soda mixture was most effective, especially after 15 minutes of soaking, but did not completely remove pesticide residue that had soaked below the surface of the apple skin. In this instance, peeling would be the best solution, but you’d then negate the benefits of the nutrients found in the skin such as polyphenols and fibre.

Do organic foods have less bacteria?

The systematic review I referenced previously also investigated the risk for contamination of produce or animal products with pathogenic bacteria. Both organic and conventional animal products were commonly contaminated with Salmonella and Campylobacter species.

Due to the use of manure over synthetic fertilizers, it was found that organic produce has a higher risk of E. coli contamination. The review also found that conventionally raised chicken and pork products have a higher risk of contamination of antibiotic-resistant bacteria, probably due to the liberal use of antibiotics. Some antibiotics are being banned for use in livestock as a precaution, particularly in the EU, but it’s debatable if their use in animals has any significant contribution to antibiotic-resistant pathogens in humans (we know this is mainly due to inappropriate antibiotic prescriptions).

Is organic food more expensive?

This is another area where region makes a big difference. Logistical costs will obviously vary depending on where you live and this can make a big impact, but let’s look at the average. According to this Consumer Reports article  (USA data), 100 different products were compared and on average organic foods were 47 percent more expensive. However, the range was large, with some organic products actually being as much as 13 percent cheaper while others cost three times the price of their non-organic counterpart.

Is organic really worth it?

In the end, this is only a question you can answer. I want to reiterate that this isn’t a black or white answer – you can certainly buy a mixture of organic and non-organic foods depending on various factors like personal preference and prices.

For my money, if there’s a similar price between foods I’d probably go for the organic food. I personally prefer to support free-range conditions for animals both for nutrition and moral ends, but I’m not sold that organic is always best. Certainly, the evidence isn’t conclusive and given the number of variables that must be considered, there’s no definitive answer across the board. I’m also wary of the placebo effect and how that might impact my perception of how healthy or tasty a food is.

Whatever you think the right choice is for your household, I hope you feel better informed after getting to the end of this article!

Thanks for reading,

Luke.