Should You Only Eat Mussels in Months With an R

Should You Only Eat Mussels in Months With an R ….Here’s the Truth

You may have heard the old saying: only eat mussels in months that contain the letter “R.” That means September through April were considered safe, while May through August were supposedly off-limits.

But is that still true today?

Let’s break down where this rule came from — and whether it still matters in modern kitchens.

Where Did the “R-Month” Rule Come From?
Before refrigeration, strict food safety laws, and regulated shellfish farming, people relied on seasonal patterns to guide what was safe to eat. Coastal communities noticed two important things:

1. Mussels Taste Different in Summer
During warmer months, mussels enter their spawning season. This biological process can make their meat:

Softer
More watery
Less flavorful
So even if they weren’t dangerous, they simply didn’t taste as good.

2. Warm Water Means Higher Toxin Risk
Summer heat can trigger algal blooms (including red tides). Mussels are filter feeders, meaning they filter large amounts of water — and along with it, microscopic algae.

Some algae produce marine biotoxins, and these toxins: