Effects of Meal Timing: Striking or Modest?

Relief, ClockEat breakfast like a king, lunch like a prince, and supper like a pauper. These immortal words date back almost 70 years to a pop nutrition icon of the early and mid 20th century – Adelle Davis. Unfortunately, the health benefits of this advice are more presumption than fact. But the legends persist. This week, the Washington Post is telling us that the effects of meal timing for weight loss can be “striking.”

This is a classic case of headline versus study. The study that supposedly supports this claim has a very different interpretation. The difference observed is “modest.” So we can’t help but note the discrepancy. Striking is more or less the opposite of modest.

Yes, There’s an Effect

Let’s step back and remember what we really know about meal timing. We can start by saying that yes, when a person eats their meals seems to have an effect on the hunger they feel and their ability to succeed in losing weight.

Two different recent studies have documented a reduction in the measures of subjective hunger when people consume more of their calories earlier in the day. Leonie Ruddick-Collins et al demonstrated this in a paper they published in September. Shortly after that, Nina Vujović et al published a similar finding.

But It’s Not Huge

Adding perspective is the most recent study – a systematic review and meta-analysis in Obesity Reviews late last month. Isabel Young and colleagues examined the effects of meal timing on weight loss outcomes. Their meta-analysis included data from nine studies and they found “that a focus on earlier intakes can result in greater short-term weight loss compared with later intakes.”

Importantly, though, they note that the effect is modest and the significance of their finding disappears if they exclude only one of the nine studies from their meta-analysis. So yes, there is likely an effect on weight loss from meal timing. But no, it’s not true to say that this effect is striking or robust.

Health Reporting or Entertainment?

This begs the question of whether the Post is looking to inform or entertain its readers with reporting on obesity, nutrition, and health. Granted, the writing needs to be engaging enough to keep people reading. But we presume that the Post is not aiming to compete with the Daily Mail for the most sensational (and misleading) headlines on this important subject.

In that case, it will be important to remember the difference between striking and modest effects.

Click here for the reporting in the Post. For further perspective on the effects of meal timing, click here and here.

Relief, Clock; painting by Jean Arp / WikiArt

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January 11, 2023