Close-up of two Rello protein bars showcasing 20g protein and creatine and collagen callouts with a sunlit grass tennis court background

Rello

What the Research Actually Shows

Creatine. Protein. Collagen. Fiber. The ingredients in every Rello bar are among the most studied in nutrition...and often the most misunderstood. No hype. No shortcuts. Just what the research says, and where it stops.

30+Years of research
5g+Daily creatine, well tolerated
5–15%High-intensity performance gain
1.2–1.6g/kg protein for active adults
Close-up of a glass bowl of creatine powder on a marble slab with wooden boards behind
Safety
01 / Safety
Safety

Is Creatine Safe?

The worries are loud: kidney damage, bloating, hormones. Most of it traces to one misread marker, creatinine. When you supplement, it ticks up. That's turnover, not kidney damage for the average adult.

The Worry"It damages your kidneys."
What Trials ShowNo evidence of adverse kidney effects at recommended doses in healthy adults.
The Worry"It makes you puffy."
What Trials ShowWater moves into the muscle, not under the skin as bloat.
The Worry"It's basically a steroid."
What Trials ShowNo action on androgen receptors. The mechanism is energetic, not hormonal.
02 / Fuel
Brain Health

The Brain Runs on the Same Fuel as Muscle

Muscle & brain both run on ATP. Creatine raises phosphocreatine, a rapid reserve that regenerates ATP. It crosses the blood–brain barrier to do the same job upstairs. Not a stimulant, it supports the metabolism for cognition.

SupplementCreatine
→
Reserve↑ Phosphocreatine
→
EnergyFaster ATP regen
Man sitting outdoors holding a bar of Rello chocolate crunch
Brain Health
★Crosses the brain barrier
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Performance
03 / Performance
Performance

Why Creatine Keeps Showing Up

Trends come and go. Creatine has endured because the result replicates. More phosphocreatine, faster ATP, higher-quality work with compounding adaptation over months.

Typical gain for high-intensity performance

0%
5%
15%

Where it works

  • Resistance, sprints, team & combat sports
  • Short, high-force efforts

Where it doesn't

  • Long endurance (different system)
  • A substitute for progressive overload
04 / Nutrition
Nutrition

The RDA Is a Floor, Not a Target

0.8 g/kg is the minimum to prevent deficiency... it was never meant to optimize muscle or recovery. Active and aging adults do better at 1.2–1.6 g/kg.

The gap for a 170 lb (77 kg) person:

Protein per day — 170 lb / 77 kg adult

RDA — prevents deficiency~62g
Optimal — muscle & longevity90–125g

Why more, with age

Anabolic resistance needs a bigger signalWhey & leucine trigger synthesis
Close-up of Rello bars mid-air landing on a kitchen scale, showing bar texture and falling crumbs against a neutral beige background
Nutrition
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Women's Health
05 / Women's Health
Women's Health

Creatine for Women

For years creatine was marketed to men. This was driven by marketing, not science. Women tend to have lower baseline creatine levels, which can make supplementation more noticeable, and it may be especially relevant across hormonal transitions like perimenopause and menopause.

The Myth"It will make women bulky."
What Research ShowsBulk takes years of heavy training. Creatine just makes your workouts count for more. Stronger, not bigger.
The Myth"It causes masculinization."
What Research ShowsCreatine isn't a hormone and doesn't touch your hormones. It's fuel your body already makes.
The Myth"It's a men's supplement."
What Research ShowsWomen naturally carry less creatine, so they may have the most to gain.
06 / Longevity
Longevity

Creatine for Aging & Sarcopenia

Muscle loss starts in your 40s and accelerates after 60. Resistance training is the cornerstone and protein is the fuel...but creatine paired with both is one of the most studied concepts for aging muscle. The key phrase is paired with training.

What it supports

  • Lean mass, strength & grip when combined with resistance training
  • Sit-to-stand and functional performance
  • Bone-related markers in postmenopausal women (2-yr RCT)

What it doesn't

  • Reverse aging or replace training
  • Build muscle without a training stimulus
  • Serve as a treatment for sarcopenia
Top-down of two Rello protein bars (Vanilla Crisp, Chocolate Crunch) showing 20g protein and creatine text on golf tees
Longevity
Hands placing a Rello protein bar, wrapper showing Rello logo and 20g protein, on a blue pickleball paddle on a court
Metabolic Health
07 / Metabolic Health
Metabolic Health

Creatine & Glucose Metabolism

Muscle is one of your largest sites of glucose disposal. Creatine plus exercise has been shown to increase GLUT-4, the transporter that moves glucose from the bloodstream into muscle. More functional muscle means more capacity to clear glucose, preserving muscle supports insulin sensitivity over time.

The WorkHigh-Intensity Training
→
AdaptationIncreased GLUT-4
→
ResultBetter glucose uptake
08 / Performance
Performance

Creatine & Recovery

Performance isn't one hard session. It is how often you repeat quality work. Faster ATP regeneration between efforts helps maintain output, and research suggests creatine may attenuate markers of muscle damage and help preserve strength across dense training blocks.

Who benefits most

Athletes training several times a weekHybrid athletesBusy professionals and parentsOlder people with slower recovery
Seated man in a green cap holding a partially unwrapped chocolate snack bar with a white towel draped over his shoulder
Performance
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Brain Health
09 / Sleep
Sleep

Creatine & Sleep Deprivation

Most fixes for sleep loss are stimulants. Creatine supports the brain's energy buffering rather than firing up the nervous system. Controlled trials show it can blunt some cognitive decline under acute sleep restriction. It is not a stimulant, and not a replacement for sleep.

What it can do

  • Attenuate declines in reaction time & working memory under short-term sleep restriction
  • Support energy buffering when demand outpaces recovery

What it can't

  • Replace sleep
  • Fix chronic sleep debt
  • Act as a stimulant

The Honest Summary

We tell you what the data supports...and where it stops.

Sources: ISSN Position Stand on Creatine (2017); Common Questions & Misconceptions about Creatine (2022); Prokopidis et al., memory meta-analysis (2022); Gordji-Nejad et al., sleep deprivation (2024); Derave et al., GLUT-4 & glucose tolerance (2003); Tey et al., monk-fruit beverages (2017).

Frequently Asked Questions

How much protein is in each bar?

20g of protein from whey protein crisps and grass-fed collagen peptides.

Why only 1g of creatine?

Creatine works through daily consistency, not big single doses. 1g per bar makes it easy to build into your routine without thinking about it. Over time, that daily intake adds up.

What makes Rello different from other protein bars?

Most protein bars give you protein and call it a day. Rello is a true 4-in-1: protein, creatine, collagen, and fiber in every bar. All from whole food ingredients. No other bar on the market does that.

Are there any seed oils or artificial ingredients?

None. No seed oils, no sugar alcohols, no artificial sweeteners, no natural flavors. Just 8 real ingredients you can read and pronounce.

What does it taste like?

Chocolate almond butter with a crispy crunch. No chalky protein bar aftertaste.

Is this good for women too?

Absolutely. Creatine, collagen, protein, and fiber all support goals that matter across the board: strength, skin health, gut health, and recovery. The emerging research on creatine for women specifically is worth looking into.

When should I eat one?

Whenever works for you. Before or after a workout, between meals, or on the go. There's no wrong time.

How should I store them?

Room temperature is fine. No refrigeration needed.

What's the shipping policy?

Ships within 1-2 business days. Delivered in 3-5 business days.