Dietary Dark Matter: What Are We Eating?

Do you know what you’re having for lunch? You might think so. But in fact, the food that we are consuming is so complex, that we only have a vague idea of what’s in it. Through a project called FooDB, scientists have cataloged more than 70,000 biologically active chemicals that may be present in our food. However, most of it might be called dietary dark matter. We know it’s there and that’s about it. Albert-László Barabási is a professor of network science at Northeastern University and a lecturer at Harvard Medical School. He explains:

Our understanding of how diet affects health is limited to 150 key nutritional components. But these represent only a small fraction of the biochemicals present in our food.

Toward a More Complete Understanding of Food and Health

With a recent publication in Nature Food, Barabási explains the challenge. As an example, garlic has 67 nutritional components that USDA quantifies. Those are a small fraction of the 2,306 chemical constituents in garlic that the FooDB identifies. If you read the ingredient labeling on the food you buy, you know that those lists can get quite long – especially for highly processed foods. Even at that, you are barely scratching the surface.

It becomes overwhelming very quickly.

Responding to Complexity

Until recently, the response to all this complexity has been reductionism. Since we can’t deal with tens of thousands of biologically active compounds in our food, we’ve just ignored the dietary dark matter. So we focus on macronutrients – carbs, fats, and protein. Fighting about low-carb and low-fat diets became a bloody sport that yielded little enlightenment.

Since that wasn’t satisfying, we started digging into fats. But there are more than 300 different kinds of fatty acids, so the reductionists had their say. And thus dietary dogmatists fight about the evils of saturated versus unsaturated fats. Data on potential benefits of saturated dairy fats is a pesky nuisance. With a broad brush, we miss many fine points of nutrition.


Barabási and like-minded colleagues are proposing a third way – foodomics. Apply the technology of machine learning and big data to more fully map out the interaction of complex food constituents with human health. The complexity of nutrition is irreducible, says Barabási. To optimize personal dietary health, we need to embrace it and shine a light on the dark dietary matter in the food we eat.

Fully exploring that complexity may be essential for delivering on the promise of precision, personalized nutrition for better health.

Click here for Barabási’s paper in Nature Food, here for an exploration of dietary dark matter in New Scientist, and here for more from Inside Science.

Lunchtime, photograph © Ted Kyle / flickr

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July 23, 2020

2 Responses to “Dietary Dark Matter: What Are We Eating?”

  1. July 23, 2020 at 11:15 am, Mary-Jo said:

    RDs focus on total nutrient content of diets vs. macronutrients only. There used to be a measure called INQ, index of nutritional quality, of foods. It incorporated a food’s most prominent micronutrients in relation to it’s calorie level and gave it a score. I used it alot when working with people depending on their needs. For example, when working with a pregnant woman or even other woman of childbearing age, I would always look up Foods with a high INQ for iron and include it in recommendations. With pre-menopausal women, check foods INQ for calcium, for male athletes — foods with high INQs for calcium, iron, magnesium. I’m sure the list is endless of what other substances can be found in foods other than its first, say 10 nutrients. Investigating what substances are beneficial vs. harmful would also modify its ‘quality’ score. Interesting concept. I still think packaging contributes more harmful ‘ingredients’ than we know.

  2. July 23, 2020 at 4:17 pm, Angela Golden said:

    Ted, this is amazing and thank you for being this forward. I think it helps us all understand that truly a “calorie is not a calorie”. Every calorie has so much involved in it and besides just the amount of energy as we have used in the past (a carbohydrate is 4kcal/gram). Looking forward to reading the full article.