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Cutting Diet Guide: Lose Fat and Keep Your Muscle

Fat Loss Β· IronPeak Fitness Editorial Β· Updated 2026-08-06

Deficit sizing, protein targets, training changes, and the psychology of a successful cut.

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Set a Moderate Deficit

300–500 calories under maintenance loses roughly 0.5–1lb weekly β€” fast enough to see, slow enough to keep muscle.

None of this requires perfection. Hitting your protein and calorie targets six days out of seven, week after week, outperforms flawless weeks that end in burnout.

Protein Is Your Muscle Insurance

1g per pound of bodyweight while cutting signals your body to burn fat, not muscle. This is the single most protective habit.

Track your intake for at least one honest week before deciding anything is not working. Most stalled progress traces back to intake being different from what we assume.

Keep Lifting Heavy

Cut volume slightly if needed, but keep intensity. Lifting heavy tells your body the muscle is still needed.

Whole foods should carry the load here; supplements exist to patch specific, identified gaps β€” not to replace meals.

Manage Hunger With Food Choice

Vegetables, lean protein, potatoes, and fruit fill you for few calories. Liquid calories and snack foods do the opposite.

Adjust based on results, not feelings: weigh-ins trending the wrong way for two weeks is data, one heavy morning after a salty dinner is noise.

Diet Breaks and End Dates

Plan the cut’s end before it starts (8–16 weeks) and consider a maintenance week mid-way. Endless cutting erodes both muscle and sanity.

If you have a medical condition, a history of disordered eating, or take medication, run any significant diet change past a healthcare professional first.

Health Note

This article is educational, not medical advice. Consult a qualified healthcare professional before beginning any new diet, supplement, or exercise program β€” especially if you are under 18 or have a medical condition.

FAQ

How long until I see results from this?

Strength changes appear within weeks; visible muscle or body-composition change is typically a 2–3 month story. Judge any approach on at least 8–12 consistent weeks before overhauling it.

Do I need supplements to make this work?

No. Food, training, and sleep drive the results. Supplements like protein powder or creatine can conveniently fill specific gaps for adults β€” see our supplement guides β€” and anyone under 18 should involve a parent and doctor in any supplement decision.

Is this advice safe for teenagers?

The training and food-first principles here apply broadly, but growing athletes have specific needs. Our Teen Fitness section covers safety-first guidance, and a pediatrician or sports-medicine professional is the right resource for individual questions.

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