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Evidence-Based Only

Cutting Supplements

The supplement industry markets dozens of products to people cutting. Most are useless. Here's what the evidence actually supports — and what to skip.

The Supplement Hierarchy

1 Calorie deficit + high protein Foundation
2 Accurate food tracking Non-negotiable
3 Resistance training (maintained) Critical
4 Sleep 7–9 hours Recovery
5 Supplements (creatine, protein, caffeine) Marginal benefit

Whey Protein

★★★★★ WORTH IT
Dose
25–50g/day (to meet daily protein target)
Timing
Post-workout, or any time to hit protein target

Not magic — just a convenient, high-quality protein source. Rapidly digested, high leucine content. Use it to hit your 2.2g/kg LBM protein target, not as a replacement for whole food protein.

Casein protein before bed is useful for overnight muscle protein synthesis.

Creatine Monohydrate

★★★★★ WORTH IT
Dose
3–5g/day (no loading required)
Timing
Daily, timing is not critical

Does NOT directly burn fat, but is one of the most important supplements for a cut. Creatine maintains strength output under caloric restriction, helping you retain training intensity — which is essential for muscle preservation. Multiple meta-analyses confirm creatine reduces muscle loss during cutting.

Will add 1–2 kg of water weight initially. This is not fat. Do not stop creatine on a cut.

Caffeine

★★★★☆ WORTH IT
Dose
200–400mg/day (3–6mg/kg bodyweight)
Timing
30–60 minutes pre-workout

Caffeine increases fat oxidation during exercise, suppresses appetite, and improves training performance when calorie-restricted. The energy and performance benefits during a calorie deficit are well-documented. Cycle off every 6–8 weeks to avoid tolerance.

Get it from coffee or straight caffeine anhydrous — not overpriced pre-workouts.

Soluble Fiber (Psyllium Husk)

★★★★☆ WORTH IT
Dose
5–15g/day
Timing
Before meals, with plenty of water

Soluble fiber forms a gel in the gut, slowing gastric emptying and increasing satiety. On a cut, managing hunger is a legitimate performance challenge. 10g of psyllium husk before a meal meaningfully reduces hunger and calorie intake at that meal.

Also improves insulin sensitivity and gut health. Start with 5g and increase gradually.

Vitamin D3 + K2

★★★☆☆ WORTH IT
Dose
2,000–5,000 IU D3 / 100mcg K2 daily
Timing
With a meal containing fat

Most athletes in northern latitudes are deficient. Low Vitamin D is associated with reduced testosterone, impaired recovery, and reduced training performance. On a calorie-restricted diet, micronutrient deficiencies are more likely.

Get blood levels tested. Optimal serum levels: 40–60 ng/mL.

Magnesium Glycinate

★★★☆☆ WORTH IT
Dose
300–400mg elemental magnesium before bed
Timing
Before sleep

Magnesium is depleted through sweat. Deficiency reduces sleep quality, increases cortisol, and impairs recovery. On a cut with reduced food volume, getting adequate dietary magnesium is harder.

Use glycinate form — better absorbed, less digestive distress than oxide.

Fat Burners / Thermogenics

☆☆☆☆☆ SKIP

Proprietary blends of stimulants, herbs, and marketing. The few ingredients with any evidence (caffeine, green tea extract) are more cheaply obtained separately and dosed identically. Most "fat burner" effects come entirely from caffeine, which you can buy for $0.05/dose.

Save your money. The deficit does the work.

CLA (Conjugated Linoleic Acid)

★☆☆☆☆ SKIP

Minor effects in rodent studies, consistently fails to replicate in human trials at practical doses. Not worth the cost or the calorie addition (it's a fat source).

Save your money.

Raspberry Ketones / Garcinia

☆☆☆☆☆ SKIP

No human evidence of meaningful effect. Pure marketing supplements with no plausible mechanism at real-world doses.

Waste of money.

The Bottom Line on Cutting Supplements

Supplements are exactly what the name says — supplemental. They marginally improve results on top of a solid foundation. They cannot compensate for a bad diet, inaccurate tracking, or lack of training consistency.

The four supplements worth using during a cut: whey protein (to hit your protein target), creatine monohydrate (to maintain training performance), caffeine (for performance and fat oxidation during training), and fiber (to manage hunger).

Total cost: under $1.50 per day. Anyone selling you a $60 "shredding stack" is selling you marketing, not science.

Tracking what you eat matters more than any supplement

PlateLens AI photo tracking gives you the precision your diet needs. Available on iOS and Android.