Collagen after 50 in NZ: joints, skin, and how to choose

Collagen is everywhere right now — powders, sachets, “beauty” blends — and the marketing runs well ahead of the science. So let’s be honest about what it can and can’t do, and how to choose one if you decide it’s worth a try.

I’m Dr Roderick Mulgan, an Auckland GP and the founder of Lifeguard Health. Here’s a straight, evidence-based look at collagen for New Zealanders over 50: where the evidence is reasonable, where it’s thin, and what to look for on the label.

The short version

Collagen is the main structural protein in skin, joints, tendons and bone. From your mid-40s your body makes less of it, and for women the drop accelerates around menopause. Taking collagen won’t turn the clock back, but a daily hydrolysed-collagen supplement has reasonable evidence for supporting skin hydration and elasticity, and some promising evidence for joint comfort. If you eat well and your joints and skin are fine, you may not need it; if you want to give it a fair trial, here’s how to do it sensibly.

What the evidence actually says

Skin. This is collagen’s strongest card. A number of trials suggest hydrolysed collagen peptides can support skin hydration and elasticity over a couple of months of daily use. The effects are modest and the research is partly industry-funded, so keep expectations realistic — better hydration, not a different face.

Joints. There’s promising evidence that collagen may support joint comfort, particularly with activity, though it’s less settled than the skin research. It’s not a treatment for arthritis — if joint pain is persistent, that’s a conversation with your GP.

Bone. Early research is interesting but not yet strong enough to recommend collagen for bone health. For bones after menopause, the better-evidenced foundations are calcium, vitamin D and strength training.

The honest summary: collagen is a reasonable “may help” for skin and joints, not a proven fix. Anything promising to “reverse ageing” is overselling it.

Marine vs bovine — does it matter?

Both are hydrolysed into the same small peptides your body absorbs, so for most people the choice is about source rather than results. Marine (from fish) is popular and well absorbed; avoid it if you have a fish allergy. Bovine (from cattle) is widely used and usually cheaper. Either can do the job — what matters more is that it’s hydrolysed and you take a sensible daily dose consistently.

How to choose, and how to take it

• Form: choose hydrolysed collagen peptides (also called collagen hydrolysate) — that’s the absorbable form.
• Dose: most studies use roughly 2.5–10g a day. More isn’t necessarily better.
• Consistency: collagen works slowly — give it 8–12 weeks of daily use before judging it.
• Vitamin C: your body needs vitamin C to build collagen, so a diet with enough is sensible alongside it.
• Quality: a plain, well-sourced peptide powder beats a “beauty blend” padded with tiny doses of trendy extras.

Food first

Your body builds its own collagen from protein and vitamin C, so the foundations are unglamorous: enough protein across the day, plenty of vegetables and fruit for vitamin C, and not smoking (which degrades collagen). Bone broth gets talked up, but the amounts are modest and variable. A supplement is a top-up on good basics, not a replacement for them.

Where Lifeguard fits

I’ll be straight with you, the same way I am about fish oil: Lifeguard doesn’t make a collagen product, so I’m not going to steer you to one of ours and pretend. If you want to try collagen, use the guidance above to choose a good hydrolysed peptide.

Where our range fits is the daily foundation underneath it. Lifeguard Essentials is our doctor-formulated daily base for adults 45+, and the Lifeguard Bundle pairs it with our other core formulas. For joints specifically, see our guide on omega-3 for adults 45+ in NZ, and for the bigger picture our healthy ageing supplements guide.

A supplement supports good nutrition — it isn’t a substitute for medical care. If joint pain or a skin concern is persistent, see your GP.

Frequently asked questions

Does collagen actually work for skin and joints?

For skin, there’s reasonable evidence that daily hydrolysed collagen can support hydration and elasticity over a couple of months — modest, not dramatic. For joints, the evidence is promising but less settled. It may help; it’s not a guaranteed fix, and it’s not a treatment for arthritis.

Marine or bovine collagen — which is better?

For most people, results are similar because both are hydrolysed into the same absorbable peptides. The choice is mainly about source and price — marine if you prefer fish-derived (not if you have a fish allergy), bovine if you want a cheaper, widely available option.

How much collagen should I take a day?

Most studies use roughly 2.5 to 10 grams of hydrolysed collagen peptides daily. Pick a sensible dose in that range and, importantly, take it consistently — collagen works slowly.

Can I get collagen from food?

Your body makes its own collagen from protein and vitamin C, so a diet with enough of both is the foundation. Bone broth contains some, but in modest and variable amounts. A supplement is a top-up, not a substitute for good basics.

When will I notice a difference?

Give it 8 to 12 weeks of daily use before deciding. If you’ve seen nothing by then, it’s probably not doing much for you.

Written by Dr Roderick Mulgan, NZ GP and founder of Lifeguard Health. This article is general information, not medical advice. For persistent joint or skin concerns, see your GP.