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They're Growing Every Day. Make Sure Their Nutrition Keeps Up.

Growth asks a lot of a small body. One ready-to-pour packet gives kids 6g of protein for growing muscles, bioactive collagen peptides for developing bones, and 4g of gentle fiber, all dosed for ages 4 to 12.

Support Their Growth
45 Day Money Back Guarantee**
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Growth asks a lot of a small body. One ready-to-pour packet gives kids 6g of protein for growing muscles, bioactive collagen peptides for developing bones, and 4g of gentle fiber, all dosed for ages 4 to 12.

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Support Their Growth
45 Day Money Back Guarantee**

Signs They're In A Growing Season

A 4-year-old and a 12-year-old aren't the same kid, and their nutrition shouldn't be either. Growth comes in bursts, and each one asks for more than the last.

Signs They're In A Growing Season

A 4-year-old and a 12-year-old aren't the same kid, and their nutrition shouldn't be either. Growth comes in bursts, and each one asks for more than the last.

New Shoes. Again.

The sneakers you bought in August don't fit by November. When kids are growing that fast, they're building muscle, bone and connective tissue all at once, and that takes protein.

Hungry An Hour After Dinner

A growth spurt often shows up as a bottomless appetite. Protein and fiber together help them feel full between meals, so the next snack isn't the only thing filling the gap.

Growing Fast On A Small Appetite

Some kids grow just as fast while eating like birds. When the plate comes back half full, a drink they already like is the easiest way to get protein and fiber in.

Every Season Is Sports Season

Soccer in the fall, basketball in the winter, swim in the summer. Active kids use fuel for play and for growing at the same time. 6g of complete protein supports growing muscles without a sugary sports drink.

Bones Doing The Heavy Lifting

Childhood is when the frame gets built. Bioactive collagen peptides support bone development and connective tissue during rapid growth.

The Fiber Gaps Nobody Grows Out Of

Only about 5% of kids meet the fiber recommendation, one of the biggest gaps of any age group. 4g of gentle, five-source fiber supports healthy digestion and regularity while they grow.

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The Science Behind Growing Strong

How This Helps*

Muscle is built from amino acids, and growing kids need a steady supply. One protein source can't cover every job, so this blend uses three, at a dose sized for a child.

⚡ Whey Protein Isolate for fast-absorbing protein after play.

⏳ Yeast Protein for a steadier, sustained supply.

💪 A complete amino acid profile supports growing muscles.

Kids' Protein + Fiber + Collagen Protein + Fiber + Collagen 8-in-1 Mix Fuel for Kids

Tear, pour, done. A ready-to-pour liquid packet that disperses instantly in water, juice or sparkling water. No scooping, no clumps, no blender.

Protein for growing muscles Protein for growing muscles
6g

A growing body that trains needs protein for two jobs at once: growing and recovering. One protein source cannot cover fast, sustained and structural needs, so we use three.

Collagen for growing bones Collagen for growing bones
Built-In

Collagen is the main structural protein in bone and connective tissue. During years of rapid growth, the frame is doing a lot of building.

Gentle fiber for a healthy gut Gentle fiber for a healthy gut
4g

4g spread across five gentle, low-FODMAP sources. Fiber is one of the biggest gaps in kids' diets, and it doesn't close on its own as they get bigger.

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Quantity

30 Servings Per Bottle

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10 servings of Electrolyte Drink Mix For The Whole Family.

Rapid Hydration Electrolyte Support - Gift
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First Day - Kids' 3-in-1 Pre+ Post+ Probiotic

First Day - Kids' 3-in-1 Pre+ Post+ Probiotic

To support immunity, digestion, and oral health.

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Kids' Daily Hydration + Focus with Iron (do not publish)

Kids' Daily Hydration + Focus with Iron (do not publish)

Support for hydration, focus & balanced energy.

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Ingredients

We are thoughtful about the ingredients we select, use REAL organic fruits & vegetables, and keep out long lists of ingredients that can't even be pronounced.

Organic Superfoods Blend: Apple, Kale, Broccoli, Spinach, Carrot, Parsley, Beet, Green Cabbage, Raspberry, Blueberry, Strawberry, Tomato, Aronia Berry, Chlorella, Maca, Moringa, Reishi Mushroom, Cordyceps Mushroom, Lion's Mane Mushroom, Turmeric, Ginger.



Other Ingredients: Tapioca Syrup‡, Cane Sugar‡, Water, Pectin, Citric Acid, Natural Flavors, Superfood Powdered Blend‡ (Apple‡, Kale‡, Broccoli‡, Spinach‡, Carrot‡, Parsley‡, Beet‡, Green Cabbage‡, Raspberry‡, Blueberry‡, Strawberry‡, Tomato‡, Aronia Berry‡, Chlorella‡, Maca‡, Moringa‡, Reishi Mushroom‡, Cordyceps Mushroom‡, Lion's Mane Mushroom‡, Turmeric‡, Ginger‡), Carrot and Blackcurrant and Red Bell Pepper Juice for Color.
‡Organic

Free From The Top 9 Allergens: We are dairy-free, soy-free, egg-free, gluten-free, peanut-free, tree nut-free, fish-free, shellfish-free, and sesame-free.

Supplement Facts
Supplement Facts
Subscription Details

You'll receive a stylish refillable bottle on your first order, then receive our eco-friendly refill pouches every 30 days on a physician-recommended schedule.

Plus, you'll receive these benefits:

  • Savings every single month.
  • Free shipping on your first order.
  • Easy management - skip or pause whenever you need.
  • VIP access to sales, gifts, early access & more.
  • Cancel anytime.

Three Crucial Components To Support Growing Kids

Growing takes material: protein for muscle, collagen for the frame, and fiber to keep everything running. Most kids' products cover one. We put all three in one packet, sized for a child.

4g
The Muscle

Protein

6g from a complete protein blend with the amino acids growing muscles are made from. Sized for a 4 to 12 year old, where an adult tub pours 40 to 60g.

4g
The Foundation

Fiber

4g spread across five gentle, low-FODMAP sources. Fiber is one of the biggest gaps in kids' diets, and it doesn't close on its own as they get bigger.

Built-In
The Frame

Collagen

Bioactive collagen peptides inside the protein blend, supporting bone development and connective tissue during the years kids grow fastest.

Trusted By Experts and Families Like Yours

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Why Should You Choose First Day?

Active kids usually end up with an adult protein tub in one cabinet and a fiber supplement nobody takes in the other.

First Day
Adult Protein Powders
Dissolves instantly, no blender
No added sugar
Gluten-free and non-GMO

BEFORE IT BECOMES A PROBLEM

A growing kid’s body is building faster than almost any food routine can keep up with. Protein, fiber and collagen are what it builds from.

Bio-Matched™ formulates for what’s developmentally next — so the foundation is there before it’s tested.