Can onions and hawthorn be eaten together?
Generally speaking, onions and hawthorn can be consumed together, with attention to moderate intake. The detailed analysis is as follows:

Onions are rich in sulfides, flavonoids, and other substances, which can lower blood lipids, inhibit platelet aggregation, and improve cardiovascular health. Hawthorn contains abundant organic acids and flavonoids, which not only can promote gastric juice secretion and enhance gastrointestinal digestion, but also help lower blood lipids and soften blood vessels. When consumed together, they can more effectively reduce blood lipids, improve blood circulation, stimulate appetite, aid digestion, and relieve food stagnation through the acidic stimulation of hawthorn and the digestion-promoting components of onions.
However, due to its strong acidity, hawthorn should not be consumed in large quantities on an empty stomach to avoid irritating the gastric mucosa and causing discomfort such as excessive stomach acid and stomach pain. Additionally, since both ingredients have lipid-lowering effects, individuals with already low blood lipid levels should consume them cautiously to prevent further reduction in blood lipids.