You can drink three liters a day and still have skin that feels like paper by four in the afternoon. That's the observation behind this post, and it's a better starting point than any water-tracking app. Hydration isn't only how much fluid goes in. It's what your body can absorb, hold and use once it's there.
This post covers what the water research shows and who it helps, where minerals and salt fit, and why warm mineral-rich food does something a cold glass doesn't. Then the arithmetic on broth, glycine and collagen, and a sample day in a table.
Eat Your Hydration is Andra Sitoianu's phrase and her movement. She's a certified naturopath who writes The Bioavailable Naturopath on Substack, and it's one of the four things she puts on her masthead. We're borrowing the frame, adding the general research, and pointing you at her for the recipes.
Where this comes from. This post draws on the public writing of Andra Sitoianu, The Bioavailable Naturopath, in particular her free post Your Gut Is Not Weak. Your Breakfast Is Cold. We paraphrase her framing, add the general research, and link her posts so you can read her in her own words; her paid guides carry her full protocols. Educational content, not medical advice.
Why a bigger water bottle isn't the whole answer
Her Eat Your Hydration summer guide opens on a pattern she says she kept meeting in practice: people doing everything they'd been told about hydration, carrying the big bottle, tracking the intake, and still not well. That's the premise, and the rest of that guide, including her ten recipes, sits behind her paywall.
Her working definition comes from the free post instead, and it's the load-bearing line of this whole subject: hydration is the body's ability to absorb, retain and convert fluids into energy and function. Three verbs, not one number. She argues warm, salted, mineral-rich soups do that better than cold drinks, particularly first thing in the morning.
I like the frame because it moves the question from "how much" to "with what." Water arriving with minerals, protein, fat and a little salt behaves differently in your gut than water alone. That's not controversial; it's why oral rehydration solutions exist.
What the water research shows
There is a trial on this, and it's more specific than the internet version. In 49 healthy women who added about 2 liters of water a day for one month, superficial and deep skin hydration improved at the face, arm and leg, and skin extensibility and recovery improved from week two. The catch is the subgroup: that benefit appeared only in the women whose habitual intake was below about 3,200 mL a day. The group already drinking more than that barely moved.
Drinking more helps skin if you were short on fluid, and does very little if you weren't. It's a small single-sex study over a month, and the authors couldn't find consistent relationships across all their measures. Which is why "just drink more water" stops being useful at a certain point, and why what's in the glass starts to matter more than the volume.
Minerals, salt and where hydration gets decided
I'm going to keep this qualitative on purpose, because there's no serious way to hand a stranger an electrolyte number in a blog post. Salt your food to taste. Drink your broth salted. If you sweat hard, replace fluid and salt afterward rather than just fluid, which is her instruction too: in her nickel detox preview she tells readers to replace electrolytes, magnesium and zinc when they're sweating deliberately.
Magnesium is the one mineral where I can give you real figures, because the NIH fact sheet is thorough. The adult RDA is 400 to 420 mg a day for men and 310 to 320 mg for women. Food sources are green leafy vegetables, legumes, nuts, seeds and whole grains, with pumpkin seeds at 156 mg and almonds at 80 mg a serving. Tap, mineral and bottled waters run anywhere from 1 mg to more than 120 mg per liter, which is a hundredfold spread and the reason the water you drink is not a neutral choice. And 48% of Americans take in less magnesium from food and drink than the estimated average requirement.
Two limits from that page: the upper limit for supplemental magnesium in adults is 350 mg a day, higher doses commonly cause diarrhea, and the fact sheet makes no claim linking magnesium status to any skin condition. Food and water first, then.
She goes further than the evidence in places, discussing magnesium carbonate in a protective framing against nickel and naming a high-magnesium bicarbonate mineral water as her own remineralizing choice. That mineral-antagonism framework is hers, not settled toxicology, and the magnesium fact sheet does not say magnesium protects against any metal. The nickel conversation lives in the eczema, nickel and filaggrin post.
Warm mornings, in her framing
Her free post is titled Your Gut Is Not Weak. Your Breakfast Is Cold, and the argument is that a cold, dry, sugary breakfast is a harder ask for a sluggish digestive system than a warm salted soup. She builds the case from ingredients: bone broth for minerals, gelatin and glycine, egg yolks for choline and micronutrient density, a cooked starch like rice congee to steady blood sugar, warming spices for circulation and digestive warmth, mushrooms for fiber, aromatics like garlic and parsley for digestive secretions, and a sour note at the end from lemon.
Some of those rationales have research behind them and some are hers. Cortisol sparing from congee, vitamin C for adrenal function, mushrooms clearing estrogen metabolites: those are her framing, and I'd hold them loosely. The pattern is the useful part, and it copies fine without any of the mechanism being true: a warm broth base, salt, a fat, a yolk or some protein, a cooked starch, aromatics, something sour at the end.
Her five recipes and the ten in the summer guide are hers to give, so I'm not reprinting them. The cold breakfast post is free and the recipes are in it. Go read them there.
Broth, gelatin and glycine, with the arithmetic
Bone broth is the center of this style of eating, so it's worth knowing what's actually established. A 2025 review in Digestive Diseases and Sciences sets out that bone broth supplies amino acids including glutamine, glycine, proline, histidine and arginine along with calcium, phosphorus, potassium, magnesium and zinc, and concludes from animal and human work that those components support gut health, reduce inflammation at the intestinal barrier and improve barrier function, particularly in inflammatory bowel disease.
Look closely at what that evidence covers. It is for the individual nutrients rather than for broth as a tested intervention. Home-made broth varies enormously, and the review notes that analyses of essential and toxic metals in animal bone broths exist, so contamination is a recognized issue. It doesn't connect broth to skin at all. That connection is a reasonable inference, not a finding.
The glycine arithmetic is worth doing slowly. A 2009 metabolic analysis calculated that collagen synthesis in a 70 kg adult needs roughly 10 g of glycine a day, while the body makes about 3 g and a typical diet supplies 1.5 to 3.0 g, leaving a shortfall of about 10 g a day across all glycine uses. The authors argue glycine should be treated as a semi-essential amino acid. That's a calculation from metabolic flux data rather than a trial, and it does not show that eating more glycine improves collagen, skin or anything else. It's a good reason to think collagen-rich foods are worth eating and a bad reason to promise anything.
One more contested idea she raises in this territory: glyphosate as a glycine mimic that interferes with connective tissue. That's a hypothesis with a published rebuttal, and it's handled properly in the barrier post rather than here.
Collagen supplements, and what the trials measured
People conflate broth and collagen supplements constantly, so let's separate them. The supplement side has real data: a 2023 meta-analysis of 26 randomized controlled trials and 1,721 participants using collagen from fish, bovine, chicken and porcine sources for 2 to 12 weeks found significant improvements in skin hydration and skin elasticity, with no significant difference between sources for elasticity.
The authors identify several biases in those trials and say large-scale randomized trials are still needed. And the detail that matters here: that's evidence for hydrolyzed collagen peptides taken by mouth. Not for bone broth, not for gelatin in food, and not about any skin disease. Two related things, two different evidence bases.
Honey: a humectant you can also eat
Honey belongs in this post because it sits on both sides of the line. It's food, and it's a humectant, which means it draws and holds water. A 2025 review of honey in dermatology counts roughly 180 compounds in it, including water, sugars, free amino acids, enzymes, minerals, vitamins and phytochemicals, and notes that manuka honey carries methylglyoxal, which tracks with its antibacterial strength. A meta-analysis of 16 studies found honey dressings improved healing of diabetic foot ulcers, and a randomized trial of medical-grade kanuka honey with glycerine in rosacea reported a 2 point or greater improvement in 34.3% against 17.4% on control.
The authors conclude more research is needed to define honey's medicinal use and optimal protocols, and there are two safety notes worth carrying: about a quarter of raw honey samples carry Clostridium botulinum spores, which is why honey isn't given to infants, and propolis-enriched products are a well-documented contact allergen. The honey chemistry in full is in the manuka honey post.
A sample day of eating your hydration
This is a shape, not a prescription. Swap anything you don't like.
| When | What it looks like | Why it's in there |
|---|---|---|
| On waking | Warm water with a pinch of salt, or a mug of warm broth | Fluid with something in it, before coffee |
| Breakfast | Broth-based soup with a cooked starch, a yolk or shredded meat, herbs, a squeeze of lemon | Her pattern: warm base, salt, fat, protein, starch, aromatics, sour finish |
| Mid morning | Mineral water, or tea with something to eat | Waters vary from 1 mg to over 120 mg of magnesium per liter |
| Lunch | Whatever you normally eat, salted to taste, with a cooked vegetable | Food is where most minerals come from |
| Afternoon | Fruit, or a glass of water if you're genuinely under-drinking | Extra water helps if habitual intake is low, not if it isn't |
| Dinner | A soup or stew once or twice a week, otherwise a normal meal | Broth supplies glycine, proline, histidine and minerals |
| After a sauna or a hard session | Fluid plus salt, not fluid alone | Her instruction, and ordinary sports nutrition |
Her own version is more personal. In a post on X she described cold extremities, dry skin and dull hair improving when she leaned on nutrient-dense liquids: kefir or raw milk in the morning, spring water rather than reverse osmosis, and juices. That's her anecdote, not a protocol, and raw dairy carries safety and legal issues we're not going to wade into.
What this does and doesn't do for skin
The evidence supports a narrow version. If you're under-hydrated, drinking more measurably improves skin hydration and elasticity. If your diet is short on minerals and protein, fixing that is good for all of you. Collagen peptides improved hydration and elasticity across 26 trials. Beyond that, the claims outrun the data fast.
What warm mineral-rich eating won't do is replace a barrier that's losing water from the outside in. Two separate jobs. A balm is fat on the surface: it slows water loss and makes tight skin more comfortable. It doesn't hydrate anything by itself, because there's no water in a balm, which is why you put it on damp skin. It also can't fix a diet.
The clinician line, plainly: skin that's cracked, weeping, infected, spreading or suddenly much worse belongs with a licensed clinician rather than with a soup recipe. So does persistent dryness with fatigue, cold intolerance or hair changes, because thyroid and iron are blood tests, not kitchen projects.
In our kitchen a pot of broth goes on most weeks between November and March. The kids drink it out of mugs because it's warm and salty, and that's reason enough.
If your skin is dry and thirsty while you work on the inside part, Honey Glow at $42 is the jar I'd hand you: tallow with cold-pressed oat oil, squalane and an oil-soluble manuka honey extract, for skin that drinks a lotion and is tight again by lunch. It's comfort care, not a treatment, and the buyer's version of that decision is in the best tallow balm for dry skin guide. Sixty days on your skin; if it disagrees, we refund it.
Questions we hear
Does drinking more water actually help skin?
It helps if you're currently drinking too little. The trial I'd cite added about 2 liters a day for a month in 49 women and improved skin hydration and elasticity, but only in the group whose habitual intake was under roughly 3,200 mL a day. Above that, more water did close to nothing.
Is bone broth good for skin?
It's good food with a thin evidence base for that specific claim. The review I'd point at establishes that broth supplies glycine, proline, histidine and several minerals and concludes those components support the gut barrier, based on work on the nutrients rather than on broth itself. It says nothing about skin, and contamination with metals is a recognized issue. Drink it because it's good; don't expect it to do a topical's job.
Is collagen powder the same as bone broth?
No, and the evidence differs. Hydrolyzed collagen peptides have 26 randomized trials and 1,721 participants behind a significant improvement in skin hydration and elasticity, with biases the authors name themselves. Bone broth has no equivalent trial base. If you want the studied version, it's the peptides; if you want the food, it's the broth, and they're not interchangeable claims.
How much salt should I be eating?
That's a question for whoever manages your blood pressure, not for me. What I'll say generally is what she says: salt your food and your broth to taste rather than avoiding salt reflexively, and after heavy sweating replace fluid with salt rather than fluid alone. Anyone with hypertension, kidney disease or a heart condition should take that to their clinician first.
Does mineral water matter, or is tap fine?
Both can be fine, and the mineral content varies a lot: the NIH fact sheet puts tap, mineral and bottled waters anywhere from 1 mg to more than 120 mg of magnesium per liter. She prefers spring water over reverse osmosis, which is a preference rather than a finding. Most of your minerals come from food either way.
Where are her actual recipes?
Her cold breakfast post is free and carries five soup recipes in full. The ten summer recipes in the Eat Your Hydration guide are behind her paywall, and we're not reconstructing paid content, so if you want those, that's her subscription and it's the right place to spend the money.
Go deeper
The barrier side of hydration is in skin barrier repair 101, and the nutrient density argument continues in nose-to-tail nutrition for skin. Digestion upstream of all of it is in stomach acid, reflux and the PPI cascade. The full reading path is the hub, Skin Terrain 101, and if you came for the fat rather than the food, that's the beef tallow for skin guide. On the sugar side, blood sugar, glycation and inflammaging follows what glucose does to collagen.
Sources
- Andra Sitoianu, The Bioavailable Naturopath (2025). Your Gut Is Not Weak. Your Breakfast Is Cold. Substack. Free in full; her hydration definition, her ingredient rationales and her five soup recipes.
- Andra Sitoianu, The Bioavailable Naturopath (2026). Eat Your Hydration, Summer Guide. Substack. Short teaser; the premise that people who drink plenty can still be under-hydrated. The ten recipes and her principles are behind her paywall.
- Andra Sitoianu, The Bioavailable Naturopath (2025). Nickel Detox: The Method Behind My Approach. Substack. Free preview; replacing electrolytes, magnesium and zinc when sweating deliberately.
- Andra Sitoianu, The Bioavailable Naturopath. X post on dry skin and nutrient-dense liquids. X. Her personal account of kefir or raw milk in the morning and spring water over reverse osmosis; we could not re-fetch this post, so it is her anecdote as recorded in our notes.
- Palma L, Marques LT, Bujan J, Rodrigues LM (2015). Dietary water affects human skin hydration and biomechanics. Clinical Cosmetic and Investigational Dermatology 8:413.
- National Institutes of Health Office of Dietary Supplements (2026). Magnesium: Fact Sheet for Health Professionals. NIH.
- Matar A, Abdelnaem N, Camilleri M (2025). Bone Broth Benefits: How Its Nutrients Fortify Gut Barrier in Health and Disease. Digestive Diseases and Sciences 70:1951.
- Melendez-Hevia E, de Paz-Lugo P, Cornish-Bowden A, Cardenas ML (2009). A weak link in metabolism: the metabolic capacity for glycine biosynthesis does not satisfy the need for collagen synthesis. Journal of Biosciences 34:853.
- Pu SY, Huang YL, Pu CM et al. (2023). Effects of Oral Collagen for Skin Anti-Aging: A Systematic Review and Meta-Analysis. Nutrients 15:2080.
- Soliman NM, Rustad AM, Bodemer A (2025). Liquid Gold: A review of the dermatologic applications of honey. Journal of Integrative Dermatology 1:154.
Brian is the founder of Craft Tallow, a small-batch tallow skincare line shipped from Cottonwood Heights, Utah, built on 100% grass-fed suet. Questions? Reply to any email from us; it lands with him.