THE STRETCH MARK MYTH

What's Actually Happening Under Your Skin — and What the Evidence Really Says Helps

Important note: This post is for educational and informational purposes only. Nothing here constitutes medical advice. Scars and stretch marks that are painful, rapidly changing, or causing you distress are worth discussing with a dermatologist. Julie is a holistic nutritionist sharing her research and perspective, not your doctor.

At least once a week I'm asked if tallow can help prevent or minimize stretch marks and scarring, and I want to spend this post untangling several things at once: what's actually happening in your skin when scars and stretch marks form, why so much of what we're sold to "fix" them doesn't hold up to the research, and where our Tallow Body Balm — which combines grass-fed tallow and castor oil together in one formula — actually fits into the picture, honestly, without overselling it.

SCARS AND STRETCH MARKS ARE THE SAME KIND OF INJURY

Here's something that surprises people: stretch marks (medically called striae distensae) are, structurally, a form of scarring. Both start the same way — the skin experiences more physical stress than its structural fibers can absorb, and something tears.

Your skin's strength and stretch come from two proteins working together in the dermis: collagen, which provides tensile strength, and elastin, which lets skin snap back into shape after it's stretched. When skin is stretched faster than those fibers can accommodate, or when skin is cut, burned, or otherwise injured, the fibers don't stretch or heal like new. They tear or get damaged, specialized immune cells called mast cells release enzymes that break down the surrounding tissue further as part of the response, and the area then heals — but it heals as scar tissue, which is never structured quite the same way as the original, undamaged skin around it.

TYPES OF SCARS

Not all scars form the same way, and knowing which type you're dealing with matters for what — if anything — will actually help.

Atrophic scars are depressions in the skin, forming when the healing process produces too little collagen to fully rebuild what was lost. These are pitted or sunken rather than raised. Acne scarring is the most common source of atrophic scars, and we'll get into their specific subtypes below.

Hypertrophic scars are raised, firm, sometimes rubbery lumps that form when the body produces roughly three times the usual amount of collagen during healing. They stay within the boundary of the original wound and often soften and flatten somewhat on their own over time.

Keloid scars are what happens when that overproduction doesn't stop at the original wound's edge — the scar tissue continues growing beyond the boundary of the injury, sometimes substantially. Keloids are more common in those with more richly pigmented skin and often run in families.

Contracture scars form after burns, when the skin pulls tight during healing, sometimes tight enough to restrict movement if it happens near a joint. These are a different category from the ones above and generally require professional care from the start.

ACNE SCARRING SPECIFICALLY

Acne scars deserve their own section because they're so common — some estimate nearly everyone experiences at least mild acne at some point, and a meaningful share of those cases leave lasting marks. About 80-90% of acne scars are atrophic (pitted), falling into three recognizable subtypes:

• Ice pick scars — narrow, deep, V-shaped, and the most common type (roughly 60-70% of atrophic acne scars). These extend deep into the skin and are, unfortunately, the most difficult type to improve.
• Boxcar scars — wider, box-like depressions with defined edges, typically from more widespread inflammatory acne.
• Rolling scars — broad, shallow, wave-like unevenness, caused by fibrous bands tethering the skin's surface down to deeper tissue.

The remaining 10-20% of acne scarring shows up as hypertrophic or keloid scars, more often on the chest, back, and jawline.

Most people with acne scarring actually have a mix of these types rather than just one, which is part of why professional treatment plans for acne scars are usually combination approaches rather than a single fix.

TYPES OF STRETCH MARKS

Stretch marks also have real clinical categories worth knowing:

Striae rubrae — the early stage. Red, pink, or purplish, sometimes slightly raised, with active blood supply and inflammation still present. This stage is the most responsive to intervention of any kind.

Striae albae — the mature stage. Pale, silvery-white, flatter, and considerably more stable and difficult to visibly change once a mark has settled here.

Striae gravidarum — the specific medical term for pregnancy-related stretch marks, worth its own mention given how common the question comes up at our table. More on this below.

PREGNANCY, WEIGHT GAIN, AND THE GENETICS NOBODY MENTIONS

Striae gravidarum affects roughly 50-90% of pregnant women, most commonly appearing on the abdomen and breasts in the second or third trimester. If you're pregnant and starting to see them, please hear this clearly: you did not cause this, and there was very likely little you could have done differently.

The research on risk factors is remarkably consistent across multiple studies, and it points overwhelmingly toward things outside your control:

• Family history is one of the single strongest predictors. If your mother had significant stretch marks in pregnancy, your odds are meaningfully higher, independent of anything else.
• Younger maternal age is associated with higher rates, interestingly — likely related to skin collagen density and hormone patterns at different life stages.
• Weight gain during pregnancy, pre-pregnancy BMI, and higher birth weight are all independently associated with higher rates — but note that this is about degree of skin stretching, not about anyone's worth or discipline. Healthy pregnancy weight gain is necessary and expected, and stretch marks are a completely normal, common possible outcome of a body doing exactly what it's supposed to do.
• Breast involvement specifically carries higher risk than marks on the thighs, for reasons not fully understood.
• Hormones matter too — estrogen, relaxin, and adrenocortical hormones during pregnancy are thought to loosen the adhesion between collagen fibers, which is part of why the third trimester in particular is a common time for new marks to appear even in people who were doing "everything right."

The same rapid-change principle applies to significant weight gain outside of pregnancy, and to the rapid muscle or height growth of puberty — the mechanism is the same regardless of the reason your skin is stretching quickly, and genetics remains one of the biggest predictors of who ends up with visible marks and who doesn't.

RED VS. WHITE: WHY TIMING CHANGES EVERYTHING

Because striae rubrae (the red, early stage) still has active blood supply and inflammation, it's meaningfully more responsive to intervention than striae albae (the mature, white stage), which is more structurally settled and harder to change. This is genuinely good news buried in a resigned-sounding fact: most stretch marks fade substantially on their own over time, moving from vivid red toward pale and much less noticeable, whether or not you do anything at all.

THE VITAMIN E MYTH

This is the part I really want people to hear, because it's one of the most repeated pieces of skincare folklore out there, and it doesn't hold up.

Vitamin E oil has a long-standing reputation as a scar and stretch mark remedy. But when researchers have actually tested it in clinical trials, the results have been consistently disappointing. One frequently cited study found that roughly a third of participants using topical vitamin E on scars developed contact dermatitis — an allergic skin reaction — from the treatment itself. Multiple dermatology reviews since have concluded there's no reliable evidence that vitamin E improves scar appearance beyond what plain moisturizing would do on its own.

Here's the likely explanation for why it has such a strong reputation anyway: vitamin E oil is, well, an oil. Keeping any scar or stretch mark well-moisturized does modestly support the healing environment — so people using vitamin E oil were getting a real, if modest, benefit from moisturizing, and crediting the vitamin E specifically for something that any similar oil would likely have done just as well.

SCAR AND STRETCH MARK TREATMENT: LEAST TO MOST INVASIVE

If you're looking at real options, here's how they stack up, roughly ordered from gentlest to most involved. This applies broadly to both scars and stretch marks, though effectiveness varies by type:

1. Daily moisturizing and massage — the gentlest tier, genuinely low-risk, with modest but real evidence for improving texture, flexibility, and comfort. This is where a consistent tallow and castor oil routine lives (much more on this below).
2. Micropore paper tape — genuinely one of the best-kept secrets in scar care, and one of the cheapest. Applying simple medical paper tape (like Micropore) over a fresh surgical incision to offload tension has real randomized controlled trial evidence behind it, showing measurably reduced scar volume and a lower rate of hypertrophic scarring compared to no tape at all. It works mechanically — tension on a healing wound is one of the known triggers for thick, raised scarring, and the tape simply takes that tension off. I was advised to do exactly this after a cosmetic procedure of my own, applying paper tape to the incision, and healed with almost no visible scar at all. If you have an upcoming procedure, this is absolutely worth asking your surgeon about.
3. Silicone gel sheets or topical silicone gel — the best-evidenced non-prescription option for scars already formed, used clinically for scar management. Requires real consistency (often 12 hours a day for 3+ months) to see results.
4. Topical retinoids (prescription-strength, applied at home) — can improve collagen remodeling in early-stage marks, though they require a prescription and consistent use, and aren't appropriate during pregnancy or breastfeeding.
5. Chemical peels — an in-office, mildly invasive option, most effective on red/early-stage marks and often used as part of a combination protocol rather than alone.
6. Microneedling — one of the more evidence-supported treatments, using controlled micro-injury to stimulate new collagen and elastin production. Professional, clinical-depth microneedling is done in a dermatologist or medical spa setting, but it's worth knowing that at-home dermarolling devices are also widely available and inexpensive (often found on Amazon for very little money). These use much shorter needles than professional treatments and aren't a substitute for them, but they're a genuinely low-cost entry point. If you go this route, please do real self-education first — proper needle length for your goal, sanitation between uses, not rolling over active acne or broken skin, and realistic expectations about the more modest results a home device will give you compared to a clinical one.
7. Subcision and dermal fillers — used mainly for rolling acne scars, where fibrous bands are physically released and the depression is filled in.
8. Laser resurfacing (fractional, CO2, or erbium:YAG) — more invasive, with real evidence for improvement, but with recovery time and a real risk of temporary or lasting pigment changes, especially in deeper skin tones.
9. Steroid injections — used specifically for hypertrophic and keloid scars, to help flatten and soften overly thick scar tissue.
10. Surgical revision (punch excision, punch elevation) — reserved for the most severe or deep scars, particularly ice pick acne scars, where physical removal and reconstruction is the only way to meaningfully change the result.

Notice where topical products, ours included, genuinely sit on this list: tier one. That's an honest, useful place to be — but it's not tier five or six, and I'd rather tell you that than let you believe a jar of balm belongs in the same conversation as microneedling or laser resurfacing.

WHERE TALLOW AND CASTOR OIL ACTUALLY FIT IN — AND WHY

Given everything above, here's where I think a genuinely good tallow and castor oil routine earns its place, without overselling it.

For hydration and barrier support (tier one, above): Grass-fed tallow is bioidentical to the fatty acid profile of human sebum, meaning it absorbs into the skin rather than sitting on top of it the way many synthetic moisturizers do. It carries fat-soluble vitamins A, D, E, and K directly into the skin barrier. Our Body Balm also includes beeswax, which plays its own specific role here: beeswax is occlusive, meaning it forms a breathable film on the skin's surface that slows water loss without suffocating the skin the way petroleum-based occlusives can. It also carries its own small amount of vitamin A, and has natural humectant-adjacent properties that help the skin underneath hold onto moisture longer. This matters because the same basic mechanism that gives silicone sheets their evidence-based benefit — hydration and occlusion, keeping the tissue's environment stable and well-moisturized — is something this combination of tallow and beeswax supports too. It won't remodel collagen the way microneedling does, but keeping skin barrier-healthy during a period of rapid change (pregnancy, growth, healing from an injury or acne breakout) is a genuinely reasonable, low-risk thing to do daily.

For calming inflammation in fresh, red marks: Castor oil's ricinoleic acid content has real, documented anti-inflammatory properties. Since striae rubrae and fresh scars are, definitionally, still in an active inflammatory stage, a castor-oil-containing balm applied consistently during this window is a reasonable, gentle choice — precisely the stage where the research shows any intervention has its best chance of making a visible difference, versus trying to do something similar once a mark has matured to the white, settled stage.

I'll share one story here, because it's stayed with me: a customer came to my table once with a still-healing scar from open heart surgery. He told me that after about a week of using our Body Balm on it daily, he felt it had visibly flattened and faded by roughly half. I want to be careful with a story like this — it's one person's account, not a clinical study, and I have no way to know how much of that was the balm, how much was simply time and normal healing, and how much was the consistent gentle massage of applying it daily (which, as we covered above, has real evidence behind it on its own). I'm not sharing it to promise you the same result. I'm sharing it because it's a genuinely lovely thing to have happen at a farmers market table, and because it's a good example of exactly the kind of fresh, still-inflamed scar where a good moisturizing and massage routine has its best real shot at helping.

For pregnancy specifically: Since striae gravidarum is so heavily driven by genetics and rate of stretch, no cream — ours included — will prevent it if your body is predisposed. What a rich tallow and castor oil balm can reasonably offer is comfort, reduced itching (common as skin stretches), and a clean, simple routine free of synthetic fragrances or questionable ingredients during a time when many women are already being more careful about what they put on their bodies.

For acne scarring aftercare: Once active acne lesions have healed (not on open or actively inflamed breakouts), a gentle tallow-based moisturizer can support the skin barrier during the same window that professional treatments like microneedling or peels are working — keeping skin hydrated and calm alongside, not instead of, those more clinically-proven options for existing scarring.

What I won't tell you: that this balm erases a mature white stretch mark, fills in an ice pick scar, or replaces a dermatologist for a keloid. It doesn't, and I'd rather you trust me on the honest stuff so you can trust me on this too.

THE REAL TALK

Stretch marks and scars are not a skin failure. They're an extremely common, mechanically predictable, often genetically determined response to your body doing something significant — growing, carrying a pregnancy, healing from an injury, surgery, or acne, changing size. Somewhere between half and the vast majority of people have them somewhere on their body.

If you want to support your skin through one of those seasons, that's a completely reasonable thing to want, and I hope this post gave you a realistic, honest picture of what actually helps, by how much, and where. But you don't owe anyone smooth, mark-free skin as proof that you took good enough care of yourself. Your body did something real. It's allowed to show it.

"Stretch marks are just tiger stripes, evidence of the fact that you did something rather extraordinary." — Unknown

Your skin tells the truth about what you've lived through. That's not a flaw to fix. That's just a body doing its job.

— Julie Conradt, Magnolia Crow Soap Co.