CoQ10 and ubiquinol are fat-soluble molecules and are best absorbed with fats or oils, which is why it is good to take them with the largest meal of the day. (The same holds true with fat soluble vitamins, like vitamin D). However, water-soluble formulations of CoQ10 and ubiquinol have been developed which don't require fats or oils and can significantly increase the amounts of CoQ10 and ubiquinol in the bloodstream. Nevertheless, it is still best to take these solubilized formulas with food. Why? Food slows down the transit time through the small intestine, which is where CoQ10 and ubiquinol (and all vitamins and minerals) are absorbed. Longer time in the intestine creates more opportunity for absorption. In addition, fatty foods stimulate the release of bile into the intestine, improving the absorption of fats and fat soluble compounds like CoQ10. So, in short, even with water-soluble formulas, it's best to take CoQ10 and ubiquinol with food. In addition to food, water-soluble formulations of CoQ10 and ubiquinol should, obviously, also be taken with water.
See our tests of CoQ10 and ubiquinol supplements, including those with water-soluble formulations, and learn more about these products in the CoQ10 and Ubiquinol Supplements Review>>