Who should not take collagen type 2? A guide to risks and contraindications

November 2, 2025 •

4 min read

While collagen is the body's most abundant protein, it is critical to understand who should not take collagen type 2 before adding it to your regimen, especially if you have allergies or other health concerns. This guide covers the specific groups for whom this supplement may be unsuitable and the reasons why.

Quick Summary

Certain individuals should avoid collagen type 2 supplements, including those with chicken or egg allergies, autoimmune disorders, or kidney disease, as well as pregnant women.

Key Points

Allergy Risk: Individuals with allergies to chicken or eggs should not take collagen type 2, as it is commonly derived from chicken cartilage.
Autoimmune Concerns: People with autoimmune diseases should be cautious and consult a doctor, as collagen may trigger an immune response.
Pregnancy and Breastfeeding: Due to a lack of safety research, pregnant or breastfeeding women are advised to avoid collagen type 2.
Kidney and Liver Disease: The high protein content of collagen can place stress on the kidneys and liver, making it unsuitable for those with chronic disease.
Dietary Restrictions: Vegetarians, vegans, and those with specific religious dietary laws (Kosher, Halal) should avoid animal-derived collagen.
Drug Interactions: Other ingredients in supplements combined with collagen may interact with medications like immunosuppressants.

Allergic Reactions and Medical Conditions

Collagen type 2, which is primarily found in and derived from cartilage, is most known for its role in joint health. However, its animal-based origin means it is not suitable for everyone, particularly those with specific allergies or certain medical conditions.

People with Chicken or Egg Allergies

One of the most significant contraindications for taking collagen type 2 is a pre-existing allergy to its source. The majority of type 2 supplements are derived from chicken cartilage, and some may also contain eggshell membrane. For individuals with a diagnosed allergy to chicken or eggs, consuming these supplements can trigger a severe allergic reaction. Symptoms can range from mild skin rashes, hives, and itchiness to more serious respiratory issues like swelling and difficulty breathing. Always check the product label for the collagen's source before consumption.

Individuals with Autoimmune Conditions

People with autoimmune disorders, such as rheumatoid arthritis or lupus, should exercise caution and consult a physician before using collagen type 2. The theoretical risk is that introducing a foreign protein could potentially stimulate the immune system, potentially worsening symptoms in susceptible individuals. This is a complex area of immunology, and while some studies have investigated collagen's effects on autoimmune joint conditions, it is crucial to proceed under a doctor's supervision.

Pregnant and Breastfeeding Women

Due to a lack of sufficient research on its effects during pregnancy and lactation, collagen type 2 is not recommended for pregnant or breastfeeding women. The safety of the supplement for both the mother and developing child has not been conclusively established, and most healthcare professionals advise avoiding it as a precautionary measure.

Those with Kidney or Liver Disease

Collagen is a protein, and individuals with chronic kidney or liver disease often need to adhere to a protein-restricted diet. Supplementing with collagen can increase the protein load, potentially stressing these organs and worsening their condition. High protein intake can also lead to complications such as kidney stones due to the amino acid hydroxyproline, which is converted to oxalate in the body.

Dietary and Ethical Considerations

Collagen supplements are inherently animal-based, which poses a clear conflict for those with specific dietary and ethical beliefs.

Vegans and Vegetarians

As collagen is exclusively derived from animal sources (chicken, marine, bovine), it is not suitable for vegans or vegetarians. While supplements are available that contain plant-based ingredients to support the body's own collagen production, they do not contain actual animal collagen.

Religious and Cultural Dietary Restrictions

For people who follow Kosher or Halal dietary guidelines, the animal source of collagen is a critical factor. Unless certified, collagen derived from pigs (porcine) or cows (bovine) would not be permissible. Those with these dietary restrictions must verify the product's source and certification.

Potential Drug Interactions and Other Risks

In addition to the above, there are other potential issues to be aware of when considering collagen type 2 supplements, especially when other medications are involved.

Potential Drug Interactions

While collagen itself has few known drug interactions, it is often combined with other ingredients like herbs, vitamins, or minerals in supplements. Some of these additives could interact with medications, such as blood thinners or immunosuppressants. It is crucial to read labels and consult a doctor before starting any new supplement, especially if you are on medication.

Choosing an Alternative to Collagen Type 2

For those who cannot take collagen type 2, other options are available for supporting joint health and overall wellness. A balanced, nutrient-rich diet is a cornerstone of this approach.

Glucosamine and Chondroitin: These are other common joint health supplements that can be used as alternatives to collagen. They provide building blocks for cartilage, though their effectiveness can vary.
Nutrient-Rich Diet: Consuming a diet rich in vitamin C (citrus fruits, bell peppers), zinc (seeds, nuts), and copper (organ meats, nuts) can help support your body's natural collagen production.
Plant-Based Options: Vegan supplements can help support collagen synthesis by providing necessary amino acids and cofactors without using animal products.
Gelatin and Bone Broth: For those without strict dietary restrictions, gelatin and bone broth are natural sources of collagen and other beneficial nutrients.

Side Effects of Collagen Type 2 vs. Other Types

To help understand the nuances, here is a comparison of different collagen types and their sources:


Feature	Collagen Type 2	Collagen Type 1 & 3	Marine Collagen (Mostly Type 1)
Primary Source	Chicken cartilage	Bovine hide, pork skin	Fish skin and scales
Main Function	Supports joint cartilage and reduces joint pain	Supports skin, hair, nails, and bones	Supports skin elasticity and bone density
Allergy Risk	Chicken or egg allergies	Beef or pork allergies	Fish or shellfish allergies
Dietary Suitability	Not suitable for vegans/vegetarians	Not suitable for vegans/vegetarians	Not suitable for vegans/vegetarians, specifically for fish allergies
Common Side Effects	Mild stomach upset, constipation	Mild digestive issues, bad taste	Mild digestive issues, fishy aftertaste

Conclusion

While collagen type 2 is generally well-tolerated and offers potential benefits for joint health, it is not suitable for everyone. Individuals with specific allergies (especially chicken or egg), autoimmune diseases, or kidney/liver problems should avoid it or use it with extreme caution under a doctor's supervision. Furthermore, pregnant or breastfeeding women and those with vegetarian or vegan diets are not good candidates for this supplement. Always consult with a healthcare professional before adding any new supplement to your routine to ensure it is appropriate and safe for your unique health circumstances.

For more comprehensive information on supplements, you can visit the National Institutes of Health Office of Dietary Supplements website: https://ods.od.nih.gov/.

Frequently Asked Questions

No, people with chicken allergies should not take collagen type 2, as most supplements are derived from chicken cartilage and could trigger a severe allergic reaction.

Individuals with autoimmune diseases should be cautious with collagen type 2, as it is a foreign protein that could potentially trigger or exacerbate an immune system response.

There is not enough reliable information to determine if collagen type 2 is safe for pregnant or breastfeeding women, so it is best to avoid it unless approved by a healthcare professional.

Excessive intake of certain types of collagen may increase the risk of developing kidney stones, especially in those with pre-existing kidney issues, due to the conversion of hydroxyproline to oxalate.

No, collagen is an animal product and is not suitable for vegan or vegetarian diets. Plant-based alternatives exist that support the body's natural collagen production.

While collagen itself has few interactions, supplement formulas often contain other ingredients that could interfere with medications, particularly immunosuppressants. Always consult your doctor.

Common side effects, which are typically mild, can include nausea, bloating, heartburn, and constipation.

You can support joint health with alternatives like glucosamine and chondroitin, a nutrient-rich diet high in vitamin C, or by consuming natural sources like bone broth if your diet allows.