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Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous logo and orange triangle brandmark.
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate in Vanilla flavor (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous logo
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate in Strawberry flavor (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate in Unflavored (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous logo
A man in a black t-shirt stands at a kitchen counter reaching for a tub of Momentous Whey Protein Isolate (Foundational & Performance, Lemon flavor) next to a tub of Momentous Fiber+ (Digestive & Gut Health) and a glass pitcher filled with a white shake, with a blender visible on the left. A colorful abstract painting hangs in the background. Bold white text overlay reads:
Momentous supplement bundle arranged on a dark surface with a moody, gym-inspired background: a large white tub of Whey Protein Isolate in Vanilla flavor (Foundational & Performance, Upgraded Formula, 1.38lb / 625g); a mid-size white tub of Fiber+ in Unflavored (Digestive & Gut Health, 13.1oz / 346g); a small dark glass bottle of Vitamin D3 (Foundational Health) with capsules spilling out in front; and a black Momentous branded shaker cup with orange triangle logo. Bold white text overlay reads:
Arnold's Ultimate Stack:
Arnold Schwarzenegger in a black t-shirt seated in a brown leather chair, looking directly into the camera with a slight smile, colorful abstract artwork visible in the background. Bold white text overlay reads:
Promotional graphic for Momentous Arnold’s Ultimate Stack featuring four supplements displayed on a neutral beige background. The stack includes Whey Protein Isolate, Fiber+ Digestive & Gut Health, Creatine for muscle performance and cognitive function, and a bottle of Vitamin D3. Headline text reads “Held to The Momentous Standard.” Supporting text explains the stack includes grass-fed whey protein isolate, high-quality creatine monohydrate, a 3-in-1 Fiber+ formula for gut support, and Vitamin D3
Whey Protein Isolate in Chocolate Flavor. Serving Size: 1 Scoop (26.2g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate 2g (less than 1% DV), Dietary Fiber less than 1g (2% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.6mcg (3% DV), Calcium 100mg (8% DV), Iron 0.7mg (4% DV), Sodium 145mg (6% DV), Potassium 130mg (3% DV). Key ingredients: Grass-fed whey protein isolate 23.3g, Pro-Hydrolase®
Momentous Whey Protein Isolate in Vanilla Flavor. Serving Size: 1 Scoop (25g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate 2g (less than 1% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.4mcg (2% DV), Calcium 100mg (8% DV), Sodium 120mg (5% DV). Key ingredients: Grass-fed whey protein isolate 23.3g, Pro-Hydrolase® proprietary blend of proteases from Bacillus sp. and Ananas comosus 200mg.
Momentous Whey Protein Isolate in Strawberry Flavor. Serving Size: 1 Scoop (24.7g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate 2g (less than 1% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.4mcg (2% DV), Calcium 100mg (8% DV), Sodium 45mg (2% DV), Potassium 90mg (2% DV). Key ingredients: Grass-fed whey protein isolate 23.4g, Pro-Hydrolase® proprietary blend of proteases from Bacillus sp. and Ananas comosus 200mg.
Momentous Whey Protein Isolate in Unflavored. Serving Size: 1 Scoop (23.6g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate less than 1g (less than 1% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.4mcg (2% DV), Calcium 100mg (8% DV), Sodium 45mg (2% DV). Key ingredients: Grass-fed whey protein isolate 23.3g, Pro-Hydrolase® proprietary blend of proteases from Bacillus sp. and Ananas comosus 200mg. Contains Milk.
Supplement Facts for Fiber+ Pure Cinnamon. Text reads: “Fiber+,” “Pure Cinnamon,” “Supplement Facts,” “Serving Size: 1 Packet (10.4g),” “Servings Per Container: 10.” “Amount Per Serving % Daily Value.” “Calories 35.” “Total Carbohydrate 8g 3%.” “Dietary Fiber 6g 21%.” “Psyllium Husk 4g**.” “Resistant Potato Starch 3.5g (Solnul®).” “Rice Bran Hull 2g.” “*Percent Daily Values are based on a 2,000 calorie diet.” “**Daily value not established.” “Other Ingredients: Cinnamon Bark Powder, Sunflower Lecithin, Reb
Supplement Facts panel for Momentous Creatine. Serving Size: 1 Scoop (5g), Servings Per Container: 30. Per serving: Creapure® creatine monohydrate 5g. Daily value not established.
Supplement Facts panel for Momentous Vitamin D in 2000IU. Serving Size: 1 Capsule, Servings Per Container: 60. Per serving: Vitamin D 50mg (2,000IU) as plant-based cholecalciferol (D3), 250% Daily Value. Other Ingredients: Organic Extra Virgin Olive Oil, Hypromellose, Candelilla Wax.
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous logo and orange triangle brandmark.
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate in Vanilla flavor (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous logo
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate in Strawberry flavor (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous
Momentous supplement bundle featuring four products on a dark background: a large white tub of Whey Protein Isolate in Unflavored (Foundational & Performance, Upgraded Formula, Dietary Supplement); a mid-size white tub of Fiber+ in Pure Cinnamon flavor (Digestive & Gut Health, 13.1oz / 372g); a small dark glass bottle of Vitamin D3 (Foundational Health, 60 Soft Capsules); and a small white tub of Creatine (Muscle Performance & Cognitive Function). All products display the Momentous logo
A man in a black t-shirt stands at a kitchen counter reaching for a tub of Momentous Whey Protein Isolate (Foundational & Performance, Lemon flavor) next to a tub of Momentous Fiber+ (Digestive & Gut Health) and a glass pitcher filled with a white shake, with a blender visible on the left. A colorful abstract painting hangs in the background. Bold white text overlay reads:
Momentous supplement bundle arranged on a dark surface with a moody, gym-inspired background: a large white tub of Whey Protein Isolate in Vanilla flavor (Foundational & Performance, Upgraded Formula, 1.38lb / 625g); a mid-size white tub of Fiber+ in Unflavored (Digestive & Gut Health, 13.1oz / 346g); a small dark glass bottle of Vitamin D3 (Foundational Health) with capsules spilling out in front; and a black Momentous branded shaker cup with orange triangle logo. Bold white text overlay reads:
Arnold's Ultimate Stack:
Arnold Schwarzenegger in a black t-shirt seated in a brown leather chair, looking directly into the camera with a slight smile, colorful abstract artwork visible in the background. Bold white text overlay reads:
Promotional graphic for Momentous Arnold’s Ultimate Stack featuring four supplements displayed on a neutral beige background. The stack includes Whey Protein Isolate, Fiber+ Digestive & Gut Health, Creatine for muscle performance and cognitive function, and a bottle of Vitamin D3. Headline text reads “Held to The Momentous Standard.” Supporting text explains the stack includes grass-fed whey protein isolate, high-quality creatine monohydrate, a 3-in-1 Fiber+ formula for gut support, and Vitamin D3
Whey Protein Isolate in Chocolate Flavor. Serving Size: 1 Scoop (26.2g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate 2g (less than 1% DV), Dietary Fiber less than 1g (2% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.6mcg (3% DV), Calcium 100mg (8% DV), Iron 0.7mg (4% DV), Sodium 145mg (6% DV), Potassium 130mg (3% DV). Key ingredients: Grass-fed whey protein isolate 23.3g, Pro-Hydrolase®
Momentous Whey Protein Isolate in Vanilla Flavor. Serving Size: 1 Scoop (25g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate 2g (less than 1% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.4mcg (2% DV), Calcium 100mg (8% DV), Sodium 120mg (5% DV). Key ingredients: Grass-fed whey protein isolate 23.3g, Pro-Hydrolase® proprietary blend of proteases from Bacillus sp. and Ananas comosus 200mg.
Momentous Whey Protein Isolate in Strawberry Flavor. Serving Size: 1 Scoop (24.7g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate 2g (less than 1% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.4mcg (2% DV), Calcium 100mg (8% DV), Sodium 45mg (2% DV), Potassium 90mg (2% DV). Key ingredients: Grass-fed whey protein isolate 23.4g, Pro-Hydrolase® proprietary blend of proteases from Bacillus sp. and Ananas comosus 200mg.
Momentous Whey Protein Isolate in Unflavored. Serving Size: 1 Scoop (23.6g), Servings Per Container: 25. Per serving: 90 Calories, Cholesterol less than 5mg (less than 1% DV), Total Carbohydrate less than 1g (less than 1% DV), Total Sugars less than 1g, Protein 20g (40% DV), Vitamin D 0.4mcg (2% DV), Calcium 100mg (8% DV), Sodium 45mg (2% DV). Key ingredients: Grass-fed whey protein isolate 23.3g, Pro-Hydrolase® proprietary blend of proteases from Bacillus sp. and Ananas comosus 200mg. Contains Milk.
Supplement Facts for Fiber+ Pure Cinnamon. Text reads: “Fiber+,” “Pure Cinnamon,” “Supplement Facts,” “Serving Size: 1 Packet (10.4g),” “Servings Per Container: 10.” “Amount Per Serving % Daily Value.” “Calories 35.” “Total Carbohydrate 8g 3%.” “Dietary Fiber 6g 21%.” “Psyllium Husk 4g**.” “Resistant Potato Starch 3.5g (Solnul®).” “Rice Bran Hull 2g.” “*Percent Daily Values are based on a 2,000 calorie diet.” “**Daily value not established.” “Other Ingredients: Cinnamon Bark Powder, Sunflower Lecithin, Reb
Supplement Facts panel for Momentous Creatine. Serving Size: 1 Scoop (5g), Servings Per Container: 30. Per serving: Creapure® creatine monohydrate 5g. Daily value not established.
Supplement Facts panel for Momentous Vitamin D in 2000IU. Serving Size: 1 Capsule, Servings Per Container: 60. Per serving: Vitamin D 50mg (2,000IU) as plant-based cholecalciferol (D3), 250% Daily Value. Other Ingredients: Organic Extra Virgin Olive Oil, Hypromellose, Candelilla Wax.
4.8
Rated 4.8 out of 5 stars
6,024

Arnold’s Ultimate Stack

30 Servings Per Container: $3.57/Serving

Complete daily foundation for strength, recovery, immunity and gut health

  • Creatine fuels strength and training capacity*
  • Fiber+ supports full-spectrum gut health*
  • Together, they strengthen your foundation
Select Protein Flavor: Chocolate
1

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“Momentous Whey Protein is easily the cleanest and best-tasting. The chocolate flavor really stands out without tasting grainy or artificial.”

Jaden V  (Verified Customer)

“The vitamin D3 level in my bloodwork has risen to a normal level, and I trust the Momentous brand to supply a clean and pure form of D3.”

Richard G (Verified Customer)

“As a regular fiber user I can say it keeps things moving as expected. Pure Cinnamon Fiber+ combined with Vanilla Protein powder is straight up horchata!”

Douglas M (Verified Customer)

Arnold’s core performance system. No shortcuts.

Four proven essentials designed to build lean muscle, increase power, strengthen bone and immune health, and support full-spectrum gut performance in one foundational daily stack.

Arnold’s Ultimate Stack:

Covering the critical systems that determine how well you train, recover, and perform. Each product in Arnold’s Ultimate Stack plays a distinct role, working together to build strength today and performance for life.

  • Strength, power & cognitive output
    Creatine Monohydrate helps regenerate ATP—the body’s primary energy source—to increase strength, power output, training capacity, and brain performance.
  • Lean muscle growth & recovery
    Grass-fed Whey Protein Isolate delivers essential amino acids for muscle repair and maintenance, with ProHydrolase® enzymes to support digestion and absorption.
  • Bone density, muscle function & immune health
    Vitamin D3 (2000 IU) enhances calcium absorption and supports skeletal strength, neuromuscular function, and immune resilience.
  • Full-spectrum gut support
    Fiber+ combines soluble fiber, insoluble fiber, and prebiotic resistant starch to nourish beneficial bacteria, strengthen the gut barrier, and support metabolic stability.

Built to The Momentous Standard®
NSF Certified for Sport®, rigorously tested, and formulated without artificial flavors or unnecessary additives—designed for daily, long-term use.

Arnold’s Ultimate Stack works by strengthening the core systems that determine performance: muscle repair, cellular energy production, bone integrity, immune resilience, and gut health. Each ingredient plays a defined role—and together they create a compounding effect.

Here’s how it works:

Whey Protein Isolate delivers rapidly absorbed essential amino acids, including leucine, to directly stimulate muscle protein synthesis and accelerate repair after training.

Creatine Monohydrate increases phosphocreatine stores inside muscle cells, allowing faster ATP regeneration—the energy source for strength, power output, and high-intensity performance. Creatine also supports cognitive energy and mental clarity.

Vitamin D3 (2000 IU) enhances calcium absorption and neuromuscular signaling, supporting bone density, muscular contraction efficiency, immune regulation, and long-term resilience.

Fiber+ provides soluble fiber, insoluble fiber, and prebiotic resistant starch to nourish beneficial gut bacteria, improve digestive efficiency, and support nutrient absorption, metabolic balance, and steady energy.

Together, these systems don’t just “support” performance—they optimize the body’s ability to train hard, recover efficiently, and adapt over time.

Arnold’s Ultimate Stack:

Arnold’s Ultimate Stack is designed to be simple, efficient, and sustainable. Take each product once daily and adjust based on body composition, training load, and protein intake.

Creatine Monohydrate (5g daily)
Supports strength, power output, and brain performance.

  • Start with 1 scoop once per day
  • Mix with water or add to your protein shake
  • Drink shortly after mixing (best within 30 minutes)

Whey Protein Isolate (1 scoop daily)
Delivers essential amino acids for muscle repair and growth.

  • Take post-workout or anytime you need protein support
  • Increase servings to meet your daily protein target

Vitamin D3 (2000 IU daily)
Supports bone density, muscle function, and immune health.

  • Take 1 capsule daily;no food required
  • Formulated with extra virgin olive oil (EVOO) to support absorption health.

Fiber+ (2 scoops daily)
Supports digestion, microbiome diversity, and metabolic stability.

  • Mix with 12–16 oz of liquid
  • Drink shortly after mixing (Fiber+ thickens the longer it sits)
  • Can be added to your protein shake

How to Combine

  • All products can be taken together
  • Many mix Creatine + Fiber+ into their Whey for convenience
  • Vitamin D3 can be taken alongside or separately

Consistency matters. Results build with daily, long-term use.

Pairs well with: Omega-3 for joint, heart, and inflammation support.

Whey Protein:

Chocolate: Grass-fed whey protein isolate, ProHydrolase®

Other Ingredients: Natural Flavors, Cocoa, Salt, Monk Fruit Extract, Stevia, Contains Milk

Vanilla: Grass-fed whey protein isolate, ProHydrolase®

Other Ingredients: Natural Flavors, Salt, Monk Fruit Extract, Stevia, Contains Milk

Unflavored: Grass-fed whey protein isolate, ProHydrolase®

Other Ingredients: Contains Milk

Strawberry: Grass-fed whey protein isolate, ProHydrolase®

Other Ingredients: Natural Strawberry Flavor, Reb M*, Beet Root/Carrot Juice Powder (For Color), Contains Milk

ProHydrolase® is a clinically researched enzyme that enhances protein breakdown and amino acid uptake.

Creatine:

Creatine: Creapure® Creatine Monohydrate

Momentous Creatine is sourced from the purest form of creatine monohydrate available with no additives, sweeteners, or other ingredients.

Vitamin D3 2000IU:

Vitamin D3 50mcg (2000 IU) (as plant-based cholecalciferol)

Other Ingredients: Organic Extra Virgin Olive Oil, Hypromellose (Capsule), Candelilla Wax 

We include a high-quality fat source (organic extra virgin olive oil) in this product to aid in Vitamin D absorption even if taken without a meal or other fat source. 


Fiber+:

Pure Cinnamon: Psyllium Husk, Resistant Potato Starch (Solnul®), Rice Bran Hull

Other Ingredients: Cinnamon Bark Powder, Sunflower Lecithin, Reb M*


Fiber+ combines three active ingredients to support complete digestive health:

Psyllium Husk: a primarily soluble fiber that supports gut regularity.

Rice Bran: an insoluble fiber that promotes consistent digestion.

Resistant Potato Starch: a prebiotic starch that fuels beneficial gut bacteria and promotes short-chain fatty acid (SCFA) production for gut barrier support.

*Reb M is a natural, plant-based sweetener with zero glycemic response or aftertaste. Our Reb M is made from fermated rice and is 250× sweeter than sugar without bloating, 2.5× sweeter than monk fruit, and made sustainably with less land, water, and crop rotation.

When to use:
Use Arnold’s Stack daily, whether you train that day or not. Consistency is key.

Onset time:

  • Whey Protein: Begins supporting muscle repair immediately after use.
  • Creatine: Cellular saturation typically occurs within 2–4 weeks of daily use.
  • Vitamin D3: Blood levels build gradually, with measurable changes in 4–8 weeks.
  • Fiber+: You may notice easier, more regular stools within 12–48 hours, with fuller microbiome and metabolic benefits building over 1–4 weeks of steady use.

Expected results:

With consistent use, you can expect support for strength, muscle recovery, gut health, and daily performance in the short term, with improvements in muscular resilience, bone health, and overall vitality developing over time. Long-term benefits are driven by daily adherence—not quick fixes.

There are 12 credible reviews and studies related to this product:

Whey Protein Isolate:

  1. Timing and distribution of protein ingestion during prolonged recovery from resistance exercise alters myofibrillar protein synthesis
  2. Whey protein isolate attenuates strength decline after eccentrically-induced muscle damage in healthy individuals
  3. Effect of whey protein supplementation on body composition changes in women: a systematic review and meta-analysis

Creatine:

  1. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine
  2. Effects of creatine supplementation and resistance training on muscle strength and weightlifting performance
  3. Effect of creatine supplementation on body composition and performance: a meta-analysis

Vitamin D3:

  1. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease
  2. Athletic Performance and Vitamin D

Fiber+:

  1. Consumption of Solnul™ resistant potato starch produces a prebiotic effect in a randomized, placebo-controlled clinical trial
  2. The Health Benefits of Dietary Fibre
  3. The Importance of Dietary Fiber for Metabolic Health
  4. Association of dietary fiber intake with all-cause and cardiovascular mortality in U.S. adults with metabolic syndrome.
Build Your Stack
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  • Limited-run flavors. No artificial sweetners
  • NSF Certified for Sport®
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  • Supports daily protein intake
  • NSF Certified for Sport®
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Frequently Asked Questions

Yes. Arnold’s Ultimate Stack reflects the full spectrum of supplements Arnold Schwarzenegger uses daily—fiber, protein, creatine, and vitamin D3—because they address the fundamentals of strength, muscle, and long-term performance.

Arnold’s Stack is designed for anyone focused on strength, muscle, and longevity—from serious athletes to everyday individuals of any age who want a simple, proven daily routine without trends or hype.

Yes. Consistent daily use is important. Fiber, Protein, creatine and vitamin D3 work by building and maintaining levels in the body over time, not just on training days.

Momentous Whey Protein Isolate is sourced from grass-fed, pasture-raised cows on European dairy farms that meet rigorous standards for animal welfare and product quality, including being free from hormones, steroids, and rBST.

The whey is cold-processed and micro-filtered to preserve its full amino acid profile while minimizing sugar, fat, and lactose. It’s also enhanced with ProHydrolase®, a clinically studied enzyme that improves digestion and amino acid absorption, helping reduce GI discomfort and maximize protein uptake.

Not necessarily. The idea that Vitamin D3 must always be paired with Vitamin K2 to “move calcium into the bones” is a common myth, not a medical requirement. Most healthy people already get enough Vitamin K through diet-leafy greens supply K1, and foods like eggs, dairy, and fermented dishes provide K2. Your body can also convert some K1 into K2 as needed.

Clinical research shows that Vitamin D alone does not cause calcium to build up in arteries, and routine Vitamin K supplementation isn’t necessary unless you have a known deficiency.

Momentous Vitamin D3 is formulated for real-world effectiveness—2000 IU of vegan D3 delivered in organic extra virgin olive oil for superior absorption.† 

It supports bone and muscle function, immune health, and calcium metabolism without unnecessary additives or hype, and can be adjusted to meet individual needs based on guidance from your healthcare practitioner.

What matters most is creatine quality, and this is where Momentous stands apart. Our creatine is made with the world’s most trusted and rigorously tested form of creatine monohydrate, produced under pharmaceutical-grade standards. It is NSF Certified for Sport®, meaning every batch is independently verified to contain exactly what’s on the label—no banned substances, no heavy metals, and no contaminants.

We also use zero fillers, flavors, or additives. Just pure, clinically-validated creatine. That purity is what makes Momentous Creatine easier to digest, more consistent in performance, and trusted by elite athletes and high-performers alike.

Some people are concerned about bloating, however creatine does not cause unwanted weight gain or bloating for most people. Any small change on the scale is typically from water being stored inside the muscle cells, not under the skin. This is actually part of how creatine supports strength, power, and recovery, and it tends to normalize with consistent use.

Yes, all of our products are third-party tested. But that’s not enough for us. That's why we created The Momentous Standard®: a higher bar for science, sourcing, and verification, backed by independent proof you can trust.

Every product in Arnold’s Stack is certified through NSF Certified for Sport®, a respected independent program that verifies label accuracy and screens for hundreds of banned substances. If a batch fails to meet these independent standards, it does not ship, because only third-party certification can truly back that promise. We also take transparency a step further by publishing third-party test results via Light Labs on individual product pages and making Certificates of Analysis (COAs) available for every batch.

We earn trust the hard way, by proving quality at every step, on every batch, with no shortcuts.

4.8
Rated 4.8 out of 5 stars
Based on 6,024 reviews
Total 5 star reviews: 5.3k Total 4 star reviews: 475 Total 3 star reviews: 138 Total 2 star reviews: 57 Total 1 star reviews: 72
96%would recommend these products
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Reviews Summary
Customers say these supplements are tasteless and dissolve easily in beverages, making them simple to incorporate into daily routines. Many appreciate the unflavored options that mix well with coffee, smoothies, or water without altering taste. Users frequently mention the products are gentle on their stomachs and don't cause bloating or digestive issues. The cinnamon fiber supplement receives particular praise for its pleasant flavor. Common feedback includes improved workout performance, energy levels, and recovery. Many reviews mention the clean formulation and third-party testing. Some note the container design makes scooping difficult when the product gets low, and a few mention slight grittiness or incomplete dissolving in water.
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6,024 reviews
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    Cody
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    Vitamin D3 2000 IU
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    5 Stars

    Great product overall would highly recommend to any of my family or friends!

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    Cody
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    Great product, delivery os always on time. Would highly recommend!

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    Joseph
    15 hours ago
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    Fiber+
    Rated 5 out of 5 stars
    5 Stars

    Works. Tastes good. Will continue to buy.

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    Sarica G.
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    Product Standouts Taste + Texture, Ease of Use, Results, Trust and Transparency
    17 hours ago
    Product Standouts Taste + Texture, Ease of Use, Results, Trust and Transparency
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    Whey Protein Isolate
    Rated 5 out of 5 stars
    Best Protein yet!

    Love this stuff! Great mixed in with my matcha latte every morning!

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    Tracy K.
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    Product Standouts Taste + Texture, Ease of Use, Results, Trust and Transparency
    17 hours ago
    Product Standouts Taste + Texture, Ease of Use, Results, Trust and Transparency
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    Fiber+
    Rated 5 out of 5 stars
    Great product

    As usual, Momentous delivers quality products and this is no exception. Provides all of the benefits as advertised. I switched from a product that I used for years and have no regrets

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