Does Collagen Help With Weight Loss for Women Over 40?

Does collagen help with weight loss for women over 40? On the direct question, the honest answer is no. Collagen is a protein, and any protein can help a little by filling you up, but when researchers have tested collagen head to head against another protein in women who were trying to change their body composition, collagen came out behind. It is a decent supplement for a few specific things. Fat loss is not one of them.

That is not the story the ads tell, and it is not the story the search results tell either. So here is what the actual trials found, including the one study people point to when they say collagen does help.

What happened when collagen was tested against another protein

This is the trial that matters most for the question, because it was run in exactly the group asking it.

Researchers randomly assigned 37 women with overweight, average age 41, to either whey protein or hydrolyzed collagen for eight weeks. The two supplements were matched for calories and for grams of protein, so the only real difference was protein quality. Body composition was measured by DEXA scan.

The whey group lost android fat, the fat around the middle, and the collagen group did not. BMI actually rose slightly in the collagen group. The authors' own conclusion was that collagen may not be an effective supplement for women with overweight who are trying to change their body composition (Giglio, 2019).

Same calories. Same protein grams. Different result. That is about as clean a test of the question as you will find, and it does not favor collagen.

Does collagen burn belly fat?

No. Nothing you drink burns belly fat, and in the one trial above that measured belly fat directly with a DEXA scan, collagen was the arm that did not move it.

The reason this claim keeps circulating is that collagen gets described as a protein that supports lean muscle, and more muscle is loosely linked to a higher metabolic rate. The chain has a weak link in it, which we will get to.

The one trial that did show fat loss

There is a real study on the other side, and it deserves a fair hearing.

Seventy-seven premenopausal women did 12 weeks of resistance training three days a week. Half took 15 grams of specific collagen peptides daily, half took a placebo. Both groups gained fat-free mass and lost body fat, which is what strength training does. The collagen group did significantly better on both, plus hand grip strength (Jendricke, 2019).

Three things to hold alongside that result. The comparison was against a placebo, not against an equal amount of ordinary protein, so it cannot tell you whether collagen beat a scoop of whey or an extra serving of Greek yogurt. Everyone in it was lifting weights three times a week, which is the part doing most of the work. And the research group behind this line of trials has long-running ties to a collagen manufacturer, a pattern that runs through most of this literature, which we go through in detail in our honest read on what the collagen trials actually found.

It is a real finding. It is not evidence that collagen is a weight loss supplement. It is evidence that lifting weights works, possibly a bit better with 15 grams of extra protein.

Does collagen keep you full?

A little, and there is a strange twist in the data.

In a 36 hour metabolic chamber study, 23 adults ate diets built around either gelatin, which is cooked collagen, or casein, a complete milk protein. On the lower protein version of the diets, gelatin suppressed hunger 44 percent more than casein. But the gelatin diet also left people in a worse protein balance, meaning their bodies had less to work with for building and repair (Hochstenbach-Waelen, 2009).

That is the trade in one sentence. Collagen may quiet appetite slightly better than a complete protein, and it does a worse job feeding your muscle.

And appetite ratings are not the same as eating less. In a separate crossover trial, gelatin did not reduce how much people actually ate at the next meal compared with a control, while whey protein did (Akhavan, 2010).

The muscle problem, which matters more after 40

Here is the weak link in the muscle-and-metabolism argument.

Collagen is an incomplete protein. It is very low in leucine, the amino acid that acts as the switch for muscle building, and it contains no tryptophan at all. In the trial with the women above, the collagen supplement delivered about 0.1 grams of leucine while the whey supplement delivered 2.6 grams (Giglio, 2019). Both were labeled around 25 grams of protein.

What that means in practice was tested directly. Older adults spent a week in energy balance, then two weeks eating 500 fewer calories a day with their step count cut, while taking either whey protein or collagen peptides. Both groups lost leg lean mass during the restriction. When normal activity resumed, only the whey group regained lean mass and only the whey group increased muscle protein synthesis (Oikawa, 2018).

That is the scenario most women over 40 are actually in when they use a collagen scoop. Eating less, moving a bit less than usual, hoping to keep muscle. Collagen did not do that job.

Muscle is also the thing that most needs protecting in this decade, because what changes in perimenopause is body composition more than metabolic speed. Losing weight while losing muscle is how women end up smaller, weaker, and heavier again a year later.

How much collagen a day, and does the dose change anything

The doses used in research are 5 grams a day for bone, 10 grams for most skin studies, and 15 grams in the training trial above. Almost every product sits somewhere in that range, so you are unlikely to be underdosing.

For weight specifically, a bigger scoop does not fix the problem, because the problem is not the amount. It is the amino acid profile. Twenty grams of collagen still has almost no leucine in it.

If you want a scoop of protein to help you hold muscle while the weight comes off, whey, casein, soy, or a pea and rice blend all do that job better for the same money. Our guide to how much protein women actually need at every age has the daily targets by life stage, and they go up, not down, in midlife.

How long would it take to see anything

For skin, the trials generally run 8 to 12 weeks before differences show. For bone, the study below ran a full year.

For weight, there is no timeline to give, because the effect being waited for has not been demonstrated. If you have taken collagen daily for three months and the scale has moved, the deficit moved it.

Does collagen make you gain weight?

Not by itself. A scoop is usually 35 to 70 calories. Nobody gains weight from that.

Where it quietly adds up is the coffee it goes in. A collagen creamer with sugar, or a collagen latte, can run 150 calories or more, taken daily on top of everything else. If the scoop replaces part of a meal's protein, it is roughly calorie neutral. If it is added on top, it is added calories, same as anything else.

What collagen is actually good for after 40

This is worth saying clearly, because "it does not help you lose weight" is not the same as "it does nothing."

Bone has the most interesting data for this age group. In a 12 month randomized trial, 131 postmenopausal women with age-related bone loss took either 5 grams of specific collagen peptides or a placebo. Bone mineral density in the spine and femoral neck improved in the collagen group compared with the control group, and the bone turnover markers moved in a favorable direction (König, 2018). One trial is not a settled question, and this one shares the industry ties described earlier, but it is a real randomized result in the right population. If bone is your concern, start with what to eat to protect your bones through menopause and treat collagen as an add-on rather than the plan.

Skin has the largest body of human evidence, and joints have moderate evidence in people with activity-related knee pain. Both are covered in the full breakdown linked above.

So what actually moves the number after 40

The things that keep showing up in the trials are unglamorous. Enough total protein, spread through the day. Strength training two or three times a week, which is what made the collagen study's participants gain muscle in the first place. Sleep. A deficit you can hold for months rather than weeks. We went through the evidence for each of these in what actually changes about weight loss for women over 50, and the same rules apply from 40 on.

If you like collagen and it fits your budget, there is no reason to stop. Take it for your skin, your joints, or your bones, and take it on top of your protein target rather than as part of it, so the amino acids your muscle needs still come from food or a complete protein. Just do not expect it to be the thing that changes the scale, because when researchers have looked, it has not been.

For more evidence-first breakdowns like this one, browse our supplement guides, minus the hype.

This article is general information, not medical advice. Talk to your doctor or a registered dietitian about your own situation, especially before starting a supplement or changing a prescribed medication. Research cited was retrieved from PubMed.

References

• Giglio BM, et al. Whey protein supplementation compared to collagen increases blood nesfatin concentrations and decreases android fat in overweight women: a randomized double-blind study. Nutrients. 2019. PMID: 31480676
• Jendricke P, et al. Specific collagen peptides in combination with resistance training improve body composition and regional muscle strength in premenopausal women: a randomized controlled trial. Nutrients. 2019. PMID: 31010031
• Oikawa SY, et al. A randomized controlled trial of the impact of protein supplementation on leg lean mass and integrated muscle protein synthesis during inactivity and energy restriction in older persons. American Journal of Clinical Nutrition. 2018. PMID: 30289425
• Hochstenbach-Waelen A, et al. Single-protein casein and gelatin diets affect energy expenditure similarly but substrate balance and appetite differently in adults. Journal of Nutrition. 2009. PMID: 19864402
• Akhavan T, Luhovyy BL, Anderson GH. Effect of drinking compared with eating sugars or whey protein on short-term appetite and food intake. International Journal of Obesity. 2010. PMID: 20733582
• König D, et al. Specific collagen peptides improve bone mineral density and bone markers in postmenopausal women: a randomized controlled study. Nutrients. 2018. PMID: 29337906