Why Do Collagen Supplements Upset My Stomach

Low stomach acid is caused by long-term use of antacid, excess refined carbs, overeating, constant snacking, excess alcohol consumption, nutrient deficiencies, and H. pylori infection. These cause irritation to gastric mucosa. Sensitivity to supplements is one of the potential side effects. It means HCl supplementation (Betaine HCl) is needed. But don’t use this if you have ulcer. Heal the gut lining first for about 4 weeks or more before taking HCl supplement.

Another reason is Vitamin C deficiency. Vitamin C is important in the synthesis of collagen. Cooked food has less to no vitamin C because it is heat-sensitive. Eat more raw foods like vegetable salad and fruits than cooked food.

It could also be caused by the inability of the liver to process the collagen. The liver is very important organ to process carbohydrates, protein, fats, and toxins. I had this experience that I cannot tolerate Vitamin D3 supplement (fat-soluble vitamin). I got bumps behind my neck. It subsided when I stopped D3. I also can’t tolerate oregano with olive oil (fatty acid) in it. But I can tolerate B vitamins and NAC, they are water-soluble vitamins. At the time, I thought my liver hadn't fully recovered yet. So, eat more foods for your liver. Try fresh juice with beets.

The last is gene variant. COL1A1, COL1A2 and ADAMTS2 are variants that can’t process collagen. In holistic functional medicine, we look for gene variant as the last step if treating the gut and nutritional deficiencies don’t work. If you can’t process collagen, it means you need to stop taking it, that’s the concept.

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