Is l-glutamine 500mg capsules profitable to sell on Amazon United States?

The niche generates $13K/yr across 13 tracked products. 90-day search growth is +0.4%. Flapen's verdict: Skip it (45/100).

How competitive is the l-glutamine 500mg capsules niche?

11 brands and 34 sellers compete. The top 5 products take 66% of clicks and top 5 brands hold 77% of demand.

What do buyers complain about in l-glutamine 500mg capsules?

Top complaints mined from reviews: Dosage, Functionality-Overall, Ingredients-Overall. The return rate is 0.0%.

When does demand for l-glutamine 500mg capsules peak?

Demand peaks in Sep–Oct; the busiest month runs 2.3× the quietest.

What does it cost to enter the l-glutamine 500mg capsules niche?

Listings span $9.35–$26.55; the average listing price is $17.06 (sweet spot $15–$100). The average incumbent carries 2,310 reviews — the moat a new listing must climb.

L-glutamine 500mg Capsules

Skip it

A small market ($13K/yr) — this niche doesn't clear our bar today.

Returns

Incredible0.0%

return rate — above 5% kills the launch gate

Conversion

Incredible14.3%

search→purchase rate — share of searches ending in a sale

Avg price

Great$17.06

avg listing price — sweet spot $15–$100

Price range

Good$9.35–$26.55

cheapest to priciest tracked listing — scored on the share inside $15–$100

Brand share

Okay77%

top-5 brand share — brands hold most of the demand

Review moat

Okay2,310.15

avg incumbent reviews — the moat a new listing must climb

Competition

Okay66%

top-5 click share — leaders hold, buyers still browse

Growth

Okay+0.4%

90-day search growth — must beat 0% to launch

Quality gap

Okay4.6★

avg incumbent rating — lower means beatable quality

Market size

Bad$13K

$13K/yr · 5K searches

Is l-glutamine 500mg capsules profitable on Amazon?

According to Flapen's Amazon United States niche tracking, l-glutamine 500mg capsules is a $13K/yr Amazon United States market (5K searches/yr). The top 5 brands hold 77% of demand. Demand peaks in Sep–Oct. Verdict: Skip it — 45/100.

Data updated Jul 25, 2026 · scored weekly · How we score niches

l-glutamine 500mg capsules market size & sales

Units sold, revenue, conversion and listing quality across the tracked shelf.

Units sold / yr: 500–750; avg 0–100/product
Revenue / yr: $9K–$13K; units × avg price
Conversion rate: 14.3%
Avg BSR: #100
Page quality: 0%
Prime: 100%
Sponsored: 85%
Out of stock: 0.0%
Avg brand age: 106 months
Avg seller age: 181 days

Competition: brands, sellers & click share

The top 5 products take 66% of clicks — established leaders, but buyers still shop beyond them.

Brands

11 flat

Sellers

Top-5 brand share

77%

Top 20: 100%

Top-5 click share

66%

Top 20: 100%

Open market

18%

NOW Foods34%
Pure Encapsulations16%
Nutricost14%
THORNE7%
Horbäach6%
Amazing Nutrition5%
Open — no brand owns it (5 brands, 18%)

l-glutamine 500mg capsules demand & seasonality

Weekly Amazon search volume, last 98 weeks — +0.4% search growth over the last 90 days.

Peak months: Sep, Oct · busiest ÷ quietest = 2.3×

Open Trend

Top l-glutamine 500mg capsules products & what they sell for

Every tracked product — its share of the shelf, its review moat, and what it sells for.

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 13 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

NOW Foods Supplements L-Glutamine 500 mg Nitrogen Transporter* Amino Acid 120 Veg Capsules

NOW Foods$9.354.5★13,166 rev

Pure Encapsulations L-Glutamine 500 mg - Supplement for Immune and Digestive Support Gut Health and Lining Metabolism and Muscle Support* - with Free-Form L-Glutamine - 90 Capsules

Pure Encapsulations$23.514.6★2,190 rev

Nutricost L-Glutamine 800mg 180 Capsules - Gluten Free Non-GMO

Nutricost$15.774.5★4,740 rev

Now L-Glutamine 500mg 300 Veg Capsules - Non-GMO Supplement - Vegan Lglutamine Caps

NOW Foods$23.974.7★1,330 rev

THORNE - L-Glutamine - Amino Acid Supplement for Immune System & GI Health - Promotes Post-Exercise Muscle Cell Repair* - Third-Party Certified - Gluten Dairy & Soy-Free - 90 Capsules

THORNE$25.054.6★1,669 rev

Newest

by launch date

Vykee Nutrition L-Glutamine Capsules 1500 mg

Vykee Nutrition$19.22172 rev

1y ago

NAKED L-Glutamine Muscle Recovery Capsules 1000mg 240 Count Made in The USA Non-GMO Gluten and Soy Free

NAKED$19.852,177 rev

2y ago

L Glutamine Capsules - (1000mg Servings 120 Capsules) Non-GMO Gluten Free Keto Safe Vegan Friendly Third Party Tested (for Endurance and Gut Health) by Double Wood

Double Wood Supplements$9.92542 rev

2y ago

Horbaach L Glutamine Capsules 1000mg | 180 Powder Pills

Horbäach$9.99411 rev

3y ago

Amazing Nutrition$14.9761 rev

3y ago

What reviews say buyers love and hate about l-glutamine 500mg capsules

What buyers praise and complain about, mined from review topics.

What buyers love

Quality-Overall23%

“Matches the description, good product”

Vitamin11%

“Best vitamin maker on the market”

Value For Money9%

“Good price”

Regulates Digestion6%

“HELPS GUT”

Advertised Vs Actual Product6%

“Good and as advertised”

Ease Of Chewing/Swallowing5%

“Easy on the stomach”

Efficiency4%

“Seems Effective”

Acid Regulator/Stomach Ache Relief3%

“No more bloating”

Cough Relief3%

“Its quality and works well for me in aiding recovery and gut health, easy to swallow, no after taste”

Inflammation2%

“this L Glutamine is great for wound victims”

What buyers complain about

Dosage15%

“I have learned that it is a very bad dosage amount”

Functionality-Overall10%

“Not working”

Ingredients-Overall8%

“Two bottles, different ingredients”

Quality-Overall8%

“Questionable quality control and handling”

Allergies6%

“have a corn allergy/intolerance”

Sleep Quality6%

“Makes me a bit hyper at night so I take in the morning”

Vitamin4%

“There are certain vitamins and supplements that I can live without but this isn't one of them.”

Smell4%

“Mine smelled”

Ease Of Use4%

“I cannot open the lid”

Taste-Overall4%

“Totally tasteless and not super expensive”

Top return reasons

Size-Overall33%

Inflammation33%

Dosage17%

Regulates Digestion17%

Common l-glutamine 500mg capsules questions

Is l-glutamine 500mg capsules profitable to sell on Amazon United States?: The niche generates $13K/yr across 13 tracked products. 90-day search growth is +0.4%. Flapen's verdict: Skip it (45/100).
How competitive is the l-glutamine 500mg capsules niche?: 11 brands and 34 sellers compete. The top 5 products take 66% of clicks and top 5 brands hold 77% of demand.
What do buyers complain about in l-glutamine 500mg capsules?: Top complaints mined from reviews: Dosage, Functionality-Overall, Ingredients-Overall. The return rate is 0.0%.
When does demand for l-glutamine 500mg capsules peak?: Demand peaks in Sep–Oct; the busiest month runs 2.3× the quietest.
What does it cost to enter the l-glutamine 500mg capsules niche?: Listings span $9.35–$26.55; the average listing price is $17.06 (sweet spot $15–$100). The average incumbent carries 2,310 reviews — the moat a new listing must climb.