Is glycine powder profitable to sell on Amazon United States?

The niche generates $2.0M/yr across 18 tracked products. 3 of 4 products launched in the last 360 days are still selling. 90-day search growth is -26.3%. Flapen's verdict: Worth a look (60/100).

How competitive is the glycine powder niche?

15 brands and 30 sellers compete. The top 5 products take 76% of clicks and top 5 brands hold 82% of demand.

What do buyers complain about in glycine powder?

Top complaints mined from reviews: Taste-Overall, Sleep Quality, Solubility. The return rate is 0.0%.

When does demand for glycine powder peak?

Demand peaks in Feb–Sep; the busiest month runs 1.9× the quietest.

What does it cost to enter the glycine powder niche?

Listings span $10.70–$36.31; the average listing price is $22.94 (sweet spot $15–$100). The average incumbent carries 1,022 reviews — the moat a new listing must climb.

glycine powder

Worth a look

Shows low returns (0.0%), but a failed launch gate (market size, growth, or returns) keeps it on the watch list.

Returns

Incredible0.0%

return rate — above 5% kills the launch gate

Conversion

Incredible14.5%

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

Avg price

Incredible$22.94

avg listing price — sweet spot $15–$100

Market size

Great$2.0M

$2.0M/yr · 593K searches

Price range

Great$10.70–$36.31

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

Review moat

Good1,021.67

avg incumbent reviews — the moat a new listing must climb

Quality gap

Good4.4★

avg incumbent rating — lower means beatable quality

Brand share

Okay82%

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

Competition

Bad76%

top-5 click share — a locked-up shelf

Growth

Bad-26.3%

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

According to Flapen's Amazon United States niche tracking, glycine powder is a $2.0M/yr Amazon United States market (593K searches/yr). The top 5 brands hold 82% of demand. Demand peaks in Feb–Sep. Verdict: Worth a look — 60/100.

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

glycine powder market data

Units sold / yr: 80K–100K; avg 5,000–6,000/product
Revenue / yr: $1.8M–$2.3M; units × avg price
Conversion rate: 14.5%
Avg BSR: #1,454
Page quality: 0%
Prime: 100%
Sponsored: 78%
Out of stock: 5.3%
Avg brand age: 58 months
Avg seller age: 161 days

Competition & brand share

The top 5 products capture 76% of clicks — a locked-up shelf that new listings rarely crack.

Brands

15 rising

Sellers

Top-5 brand share

82%

Top 20: 100%

Top-5 click share

76%

Top 20: 100%

Open market

16%

Nutricost27%
BulkSupplements23%
NOW Foods19%
Micro Ingredients8%
Pure Encapsulations4%
THORNE3%
Open — no brand owns it (9 brands, 16%)

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -26.3% search growth over the last 90 days.

Peak months: Feb, Sep · busiest ÷ quietest = 1.9×

Open Trend

Top glycine powder search terms

glycine powder453K/yr -29.2%13.4% conv.
glycine powder organic38K/yr -32.1%9.4% conv.
glicina en polvo9K/yr +171.7%1.7% conv.
now glycine powder13K/yr -5.1%23.4% conv.
nutricost glycine powder7K/yr -21.3%23.3% conv.
now foods glycine powder6K/yr -6.6%18.2% conv.
bulk supplements glycine7K/yr -16.9%13.2% conv.
nutricost glycine7K/yr -26.3%11.7% conv.
bulk supplements glycine powder5K/yr -7.2%17.4% conv.
glycine powder for sleep10K/yr -54.6%11.8% conv.

All search terms

Top glycine powder products on Amazon

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

Top sellers

by 90-day click share

Nutricost Glycine Powder 1lb - Non-GMO Gluten Free

Nutricost$21.804.6★1,593 rev

BulkSupplements.com Glycine Powder - Glycine Supplements Amino Acid Supplement - Unflavored & Gluten Free 3g per Serving 500g (1.1 lbs) (Pack of 1)

BulkSupplements$20.624.4★4,286 rev

NOW Foods Supplements Glycine Pure Powder Promotes Restful Sleep* Neurotransmitter Support* 1-Pound

NOW Foods$17.264.6★2,229 rev

Micro Ingredients Glycine Powder 1KG (2.2 Pounds) Glycine 1000mg Per Serving Water Soluble and Product of USA

Micro Ingredients$29.014.6★1,224 rev

BulkSupplements.com Glycine Powder - Glycine Supplements Amino Acid Supplement - Unflavored & Gluten Free 3g per Serving 1kg (2.2 lbs) (Pack of 1)

BulkSupplements$28.924.4★4,286 rev

Newest

by launch date

Glycine Powder -Glycine Supplements- Glycine Amino Acid Pure & Gluten Free - 500 Gram (1.1lb)

MS Finechem$12.8311 rev

4mo ago

Vitamatic Glycine Powder 3 000 mg Per Serving Free-Form Amino Acid Supplement Unflavored 17.6 oz (500 g) Non-GMO Gluten Free.

Vitamatic$13.0945 rev

4mo ago

Glycine Powder 300 Servings (2 lb) 3 000 mg Free-Form Glycine Per Serving Unflavored Pure Powder Non-GMO cGMP Manufactured

NatureBell$25.5574 rev

7mo ago

Nutricost NAC + Glycine Powder (250 Grams) Unflavored Gluten-Free

Nutricost$21.45119 rev

9mo ago

Essencea L-Glycine Powder 2lb Pure Bulk Ingredients | 100% L-Glycine | Premium Quality Supplement (32 Ounces) [Packaging May Vary]

Essencea$16.68126 rev

3y ago

What buyers say about glycine powder

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

What buyers love

Sleep Quality18%

“Helps me sleep”

Quality-Overall13%

“Great quality in a large tub that will last”

Solubility6%

“Easy to Mix”

Taste-Overall6%

“Pleasant taste”

Value For Money6%

“Excellent price”

Sweetness5%

“It's a great sweetener”

Ingredients-Overall3%

“The ingredients are pure”

Ease Of Use2%

“Easy to Mix”

Vitamin2%

“NOW Vitamins - Good Quality Brand”

Advertised Vs Actual Product2%

“As advertised”

What buyers complain about

Taste-Overall11%

“Weird taste”

Sleep Quality8%

“Did not help me sleep”

Solubility6%

“it did not dissolve”

Dosage4%

“the scoop & serving size appears to be 1,000mg, not 3,000mg as claimed”

Smell3%

“Product Smells Like Fish”

Functionality-Overall3%

“didnt help”

Quality-Overall3%

“There are obviously quality control issues with this company”

Side Effects3%

“Now I have dizziness and vertigo”

Flavor3%

“Anything I add it to has an altered flavor which is not good”

Artificial Sweeteners2%

“Funny enough, it taste like an artificial sweetener”

Top return reasons

Sleep Quality18%

Dosage11%

Taste-Overall11%

Muscle Pain Relief7%

Side Effects7%

Sour7%

Calcium7%

Functionality-Overall7%

Acid Regulator/Stomach Ache Relief7%

Adhesion/Stickiness7%

Common questions

Is glycine powder profitable to sell on Amazon United States?: The niche generates $2.0M/yr across 18 tracked products. 3 of 4 products launched in the last 360 days are still selling. 90-day search growth is -26.3%. Flapen's verdict: Worth a look (60/100).
How competitive is the glycine powder niche?: 15 brands and 30 sellers compete. The top 5 products take 76% of clicks and top 5 brands hold 82% of demand.
What do buyers complain about in glycine powder?: Top complaints mined from reviews: Taste-Overall, Sleep Quality, Solubility. The return rate is 0.0%.
When does demand for glycine powder peak?: Demand peaks in Feb–Sep; the busiest month runs 1.9× the quietest.
What does it cost to enter the glycine powder niche?: Listings span $10.70–$36.31; the average listing price is $22.94 (sweet spot $15–$100). The average incumbent carries 1,022 reviews — the moat a new listing must climb.