Heat oil in a 4-quart saucepan. Add garlic, onion and celery, and sauté about 5 minutes. Add all remaining ingredients except spaghetti. Stir until well mixed. Bring to a boil. Reduce heat, cover and simmer about 45 minutes or until vegetables are tender. Add uncooked spaghetti and simmer 2 to 3 minutes only.
Source: National Institutes of Health