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Bio-SynergySports & performance

Skinny Protein®, 700 g

£34.99 for 700 g at Bio-Synergy. It carries more than one active ingredient, so it is not ranked against single-ingredient products. Each price below counts one ingredient only.

What it really costs, per 25 g protein£1.57One 25 g dose is our comparison unit for protein powder. It is not a recommendation.
A day£1.57
A week£10.98
A month£47.06
A year£572.54

At one 25 g dose a day, this pack lasts 22 days. A month is 30 days, so twelve of them is not quite a year.

How we worked it out

Protein powder

  • Servings: 700 ÷ 30 per serving = 23.3
  • In the pack: 23.3 × 23.9 g = 557.7 g
  • £34.99 ÷ 557.7 g × 25 g = £1.57 per 25 g protein
  • A week £1.57 × 7 = £10.98 · a month × 30 = £47.06 · a year × 365 = £572.54
  • Amount per serving: stated on the label.

Chromium

  • Servings: 700 ÷ 30 per serving = 23.3
  • In the pack: 23.3 × 30 µg = 700 µg
  • £34.99 ÷ 700 µg × 200 µg = £10.00 per 200 µg chromium
  • A week £10.00 × 7 = £69.98 · a month × 30 = £299.91 · a year × 365 = £3648.96
  • Amount per serving: stated on the label.

L-Carnitine

  • Servings: 700 ÷ 30 per serving = 23.3
  • In the pack: 23.3 × 75 mg = 1.75 g
  • £34.99 ÷ 1.75 g × 1 g = £19.99 per 1 g L-carnitine
  • A week £19.99 × 7 = £139.96 · a month × 30 = £599.83 · a year × 365 = £7297.91
  • Amount per serving: stated on the label.

The standard dose is a comparison unit, not a recommendation. Always confirm the price on the retailer's site. How we compare everything.

How it compares: whey protein concentrate

All 160, ranked →
100% ProteinCheapest per 25 g proteinProtein Works · 18 g a serving · £17.62 a month · a pack lasts 5 months59p£84.59View at Protein Works (opens in a new tab)
Whey Protein 360Protein Works · 18 g a serving · £20.30 a month · a pack lasts 29 days68p£19.49View at Protein Works (opens in a new tab)
Whey Protein 360Protein Works · 18 g a serving · £20.30 a month · a pack lasts 29 days68p£19.49View at Protein Works (opens in a new tab)
This productBio-Synergy · 23.9 g a serving · £47.06 a month · a pack lasts 22 days£1.57shown above

Ranked purely by price per 25 g protein. 54 combination products also contain protein powder.

How it compares: other forms of chromium

Compare every product in this form →
Ionic Chromium Liquid ConcentrateCheapest per 200 µg chromiumHealf · 200 µg a serving · £23.40 a month · a pack lasts 25 days78p£19.50View at Healf (opens in a new tab)
ZipVitBerberine 1000mg with ChromiumZipVit · 6 µg a serving · £69.42 a month · a pack lasts 11 days£2.31£24.99View at ZipVit (opens in a new tab)
ZipVitBerberine 1000mg with ChromiumZipVit · 6 µg a serving · £83.25 a month · a pack lasts 4 days£2.78£9.99View at ZipVit (opens in a new tab)
This productBio-Synergy · 30 µg a serving · £299.91 a month · a pack lasts 4 days£10.00shown above

Ranked purely by price per 200 µg chromium. 40 combination products also contain chromium.

How it compares: L-Carnitine

Compare every product in this form →
Liquid L-Carnitine CapsulesCheapest per 1 g L-carnitineMyprotein · 1 g a serving · £4.44 a month · a pack lasts 4 months15p£19.99View at Myprotein (opens in a new tab)
Liquid L-Carnitine CapsulesMyprotein · 1 g a serving · £6.66 a month · a pack lasts 45 days22p£9.99View at Myprotein (opens in a new tab)
L-Carnitine 500mgLamberts Healthcare (Nature's Best) · 500 mg a serving · £15.95 a month · a pack lasts 30 days53p£15.95View at Lamberts Healthcare (opens in a new tab)
This productBio-Synergy · 75 mg a serving · £599.83 a month · a pack lasts 2 days£19.99shown above

Ranked purely by price per 1 g L-carnitine. 4 combination products also contain L-Carnitine.

On the label

Protein powder · Whey concentrate
23.9 g per serving (stated on the label)
Chromium · Other forms
30 µg per serving (stated on the label)
Pack
700 g · 23.3 servings · 30 g a serving
Cost per serving
£1.50 (23.3 servings in the pack)
More label details
L-Carnitine · L-Carnitine
75 mg per serving (stated on the label)
Barcode
5034839000660
Sold by
Bio-Synergy
What the listing says
“Specifications: 700g” · “75µg chromium” · “confirmed from the retailer's own product page, not this listing's text: amount per serving 23.9; amount unit g; amount refers to compound; units per serving 30.0; pack units 700; pack unit type gram; chromium.amount per serving 30.0; chromium.amount unit mcg; chromium.amount refers to elemental”
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One 25 g dose is our comparison unit, not a recommendation.

Price history

No price change since 21 September 2026. Checked on 29 days, most recently 20 October 2026.

Price at every check
£34.99Bio-Synergy
First recorded
£34.9921 Sept
Checked on
29 dayssince 21 Sept
Pack price at each check.
  1. First checked at Bio-Synergy: £34.99

Questions about this product

How much does Bio-Synergy Skinny Protein® cost per 200 µg chromium?

£10.00 per 200 µg chromium, from £34.99 for 700 g at Bio-Synergy, checked on 20 October 2026.

How long does one pack last?

4 days at one 200 µg dose. The pack holds 700 µg in total.

How much does Bio-Synergy Skinny Protein® cost per 1 g L-carnitine?

£19.99 per 1 g L-carnitine, from £34.99 for 700 g at Bio-Synergy, checked on 20 October 2026.

How long does one pack last?

2 days at one 1 g dose. The pack holds 1.75 g in total.

How much does Bio-Synergy Skinny Protein® cost per 25 g protein?

£1.57 per 25 g protein, from £34.99 for 700 g at Bio-Synergy, checked on 20 October 2026.

How long does one pack last?

22 days at one 25 g dose. The pack holds 557.7 g in total.

About Bio-Synergy

Founded 1997 · London, England

Bio-Synergy is a sports nutrition company founded in 1997 by Daniel Herman, who remains a director. It is based on Finchley Road in London and says its products are made in the UK.

All 29 Bio-Synergy products, priced per doseVisit Bio-Synergy (opens in a new tab)

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