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Avocado Soy Unsaponifiables (ASU) supplement
Plant Extract

Avocado Soy Unsaponifiables (ASU): Benefits, Dosage, Forms & Research

Plant Extract

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

TL;DR — Quick Answer

ASU at 300mg daily reduces osteoarthritis pain and may slow cartilage loss, supported by multiple large RCTs. Prescribed in France as Piascledine 300, it inhibits cartilage-degrading enzymes while stimulating collagen synthesis. Benefits appear after 2-3 months of use.

Key Facts

What it is
A standardized extract of avocado and soybean oils containing plant sterols, beta-sitosterol, and fat-soluble compounds
Primary benefits
  • Reduces osteoarthritis pain and disability
  • Inhibits cartilage-degrading enzymes (MMPs)
  • Stimulates collagen and proteoglycan synthesis
  • May slow structural joint deterioration
Typical dosage
300mg daily
Evidence level
Strong
Safety profile
Generally Safe

What the Research Says

ASU has one of the strongest evidence bases among plant-derived joint supplements. Maheu et al. (1998) established symptomatic efficacy in a 6-month RCT, with a notable 50% reduction in NSAID use. The same group conducted a pivotal 3-year trial (Maheu et al., 2014, n=399) demonstrating structural benefits — ASU significantly slowed hip joint space narrowing compared to placebo, providing disease-modifying evidence. Appelboom et al. (2001) confirmed benefits in a 3-month RCT. A meta-analysis by Christensen et al. (2008) included ASU among supplements with evidence supporting clinical efficacy. In France, ASU is sold as the prescription drug Piascledine 300 and has over 20 years of clinical use. ESCEO and OARSI guidelines include ASU as a recommended treatment option for OA.

Benefits of Avocado Soy Unsaponifiables (ASU)

  • OA pain reduction — Maheu et al. (1998, n=163) demonstrated ASU 300mg daily significantly reduced pain and disability in knee and hip OA over 6 months, reducing NSAID use by 50%
  • Structural joint protection — Maheu et al. (2014, n=399) showed ASU 300mg daily reduced progression of joint space narrowing in hip OA over 3 years in a large placebo-controlled trial
  • Cartilage-protective mechanism — ASU inhibits matrix metalloproteinases (MMP-2, MMP-3, MMP-13) and IL-1β, preventing enzymatic cartilage breakdown at the molecular level
  • Stimulates cartilage repair — ASU upregulates TGF-β and aggrecan expression in chondrocytes, promoting synthesis of new cartilage matrix components
  • Reduces NSAID dependence — multiple trials show ASU-treated patients significantly reduce or eliminate their use of NSAIDs and analgesics over 3-6 months
Did you know?

ASU has one of the strongest evidence bases among plant-derived joint supplements.

Forms of Avocado Soy Unsaponifiables (ASU)

FormBioavailabilityBest For
ASU 300 (Piascledine)GoodThe original pharmaceutical-grade product with the strongest clinical evidence (1:2 avocado:soy ratio)
ASU Capsules (OTC)Moderate-GoodOver-the-counter supplements — look for products standardized to 300mg with 1:2 ratio

Dosage Recommendations

General recommendation: 300mg daily of standardized ASU extract (1:2 avocado:soybean ratio)

Timing: Take with a meal to enhance absorption of fat-soluble compounds; consistent daily use for at least 2-3 months • Take with food for best absorption.

Dosage by Condition

ConditionRecommended DoseEvidence
Knee osteoarthritis300mg daily for 3+ monthsStrong
Hip osteoarthritis300mg daily for 3+ monthsStrong
OA with high NSAID use300mg daily to reduce analgesic dependenceModerate

Upper limit: 600mg daily has been studied (Maheu et al., 1998) but showed no additional benefit over 300mg

Side Effects and Safety

Safety profile: Generally Safe

Potential Side Effects

  • Mild GI discomfort (rare)
  • Allergic reactions in individuals with soy allergy
  • Very well tolerated — adverse event rates comparable to placebo in large trials

Drug & Supplement Interactions

  • No significant drug interactions reported
  • Safe to combine with glucosamine, chondroitin, and other joint supplements
  • May allow reduced NSAID dosage — discuss with healthcare provider
Check Avocado Soy Unsaponifiables (ASU) interactions with other supplements →
BenefitsDosage GuideSide EffectsTypes & FormsResearchFAQ

Related Conditions

Joint Pain

Related Supplements

GlucosamineChondroitinSAMe (S-Adenosyl Methionine)UC-II (Undenatured Type II Collagen)

Frequently Asked Questions

Is ASU the same as eating avocados and soybean oil?

No. ASU contains the unsaponifiable fraction of avocado and soybean oils — the portion that cannot be converted to soap, representing only about 1% of the oil. These concentrated plant sterols (particularly beta-sitosterol), fat-soluble vitamins, and other bioactive compounds are not present in meaningful amounts in dietary avocado or soy consumption.

Can I take ASU if I have a soy allergy?

People with soy allergy should exercise caution. While the unsaponifiable fraction undergoes extensive processing that removes most soy proteins (the allergenic component), trace amounts may remain. Consult your allergist before using ASU products if you have a confirmed soy allergy.

How does ASU compare to glucosamine for osteoarthritis?

Both have strong clinical evidence for OA. ASU has a unique advantage in disease-modifying evidence (slowing structural joint damage in a 3-year hip OA trial), while glucosamine sulfate has similar structural evidence for knee OA. They work through different mechanisms and can be combined. ASU at 300mg daily is simpler dosing than glucosamine at 1,500mg daily.

References

  1. (). Symptomatic efficacy of avocado/soybean unsaponifiables in the treatment of osteoarthritis of the knee and hip: a prospective, randomized, double-blind, placebo-controlled, multicenter clinical trial. Arthritis & Rheumatism. DOI
  2. (). Randomised, controlled trial of avocado-soybean unsaponifiable (Piascledine) effect on structure modification in hip osteoarthritis: the ERADIAS study. Annals of the Rheumatic Diseases. DOI
  3. (). Symptoms modifying effect of avocado/soybean unsaponifiables (ASU) in knee osteoarthritis. Scandinavian Journal of Rheumatology. DOI
  4. (). Symptomatic efficacy of avocado-soybean unsaponifiables (ASU) in osteoarthritis (OA) patients: a meta-analysis of randomized controlled trials. Osteoarthritis and Cartilage. DOI