Have you ever tried a fat diet?

fad diet

Meaning: A popular but short-term and extreme diet.

Examples:

1. A fad diet may help at first, but it's hard to maintain.
2. She tried a fad diet to lose weight quickly.

follow trends

Meaning: To do what is currently popular.

Examples:

1. I don’t follow trends in fashion or dieting.
2. He always follows trends on social media.

trendy

Meaning: Very popular at the moment.

Examples:

1. Fad diets are very trendy these days.
2. She bought a trendy new jacket.

severe

Meaning: Very strict or extreme.

Examples:

1. That’s a severe diet—I couldn’t do it.
2. He is on a severe workout plan.

No one to judge

Meaning: Not the right person to criticize others.

Examples:

1. I’m no one to judge someone else’s lifestyle.
2. She said she’s no one to judge and respects others’ choices.

Who knows?

Meaning: Maybe; anything could happen.

Examples:

1. Maybe I’ll try a diet someday—who knows?
2. Who knows? It might actually work out.