Sustainable Diets Are Good, But All Diets Are Bad

FNCE – the world’s largest meeting of food and nutrition experts – is winding up today in Philly. It’s an occasion where more than 10,000 dietitians, food professionals, and policymakers gather. The experience is sensory overload on food and nutrition. Without a doubt, passions run high on nutrition beliefs at this meeting. For instance, the President’s Lecture was all about the urgent need for globally sustainable diets. Gotta love those plant-based diets. Our planet’s future depends on it, says Walter Willett.

But on Monday, the house was packed for an hour and half about how bad diets are. We must challenge the food police when they tell us what we ought to be eating. Reject diet culture. Intuitive eating is the answer.

How can it be that everyone on the planet must shift to a more plant-based diet? And yet, we must resist people telling us what we should eat?

Passions and Evidence

The common thread here is passion. We are passionate about the future of the planet. Three presenters – Willett, Jessica Fanzo, and Francesco Branca – made that abundantly clear. Hunger is not going away, and yet obesity is rising. Meanwhile, excessive dependence on animal-based protein is burning up the planet. We’ve got to shift our dietary patterns. We need our plates filled with planetary health, said Willett.

If you’re looking for more support for that idea, just turn to the Proceedings of the National Academies of Sciences. Yesterday in that journal, Michael Clark et al published a study of foods linked to better human and planetary health. And guess what? For the most part, they found that healthier foods comprise the diets for healthier planet. It’s a tidy package to support the drive for healthier, plant-based diets.

Evidence for Intuitive Eating

In all honesty, the evidence for intuitive eating is a little thinner. Presenters to the full house at FNCE pointed to a systematic review by Lyndell Bruce and Lina Ricciardelli. However, the conclusion of that review is not too compelling. We need prospective studies, said the authors, to verify whether or not intuitive eating will actually deliver on promises of better health and well-being.

Intuitive eating correlates with better measures of well-being. But the available data is inadequate for proving whether intuitive eating causes better well-being, or instead, better well-being leads to more intuitive eating. It’s that age old problem of lacking evidence for distinguishing correlation from causation.

We’ve said it before. Intuitive eating sounds great. But we still need better evidence to back it up.

Passion for Dietary Concepts

Clearly at FNCE, we see lots of passion for a healthy planet, healthy diets, and intuitive eating skills. It’s all good, just so long as we keep an eye on what the evidence really says.  Overselling a good idea is a great way to kill it.

Click here for the paper by Clark et al on sustainable diets and here for the systematic review of intuitive eating. For a systematic review on the related concept of self-compassion, click here.

Your Plant-Based Powerhouse, photograph © Ted Kyle / flickr

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October 29, 2019