Precum is made mostly of water, plasma, and mucus (a lubricating substance). It is generally not as thick as semen. It contains around 20 calories, and is made up of small amounts of essential nutrients including Calcium, Citrate, Fructose, Glucose, Lactic Acid, Magnesium, Potassium, Protein, and Zinc. Precum and semen contain nutrients because they travel a massive distance in the vagina while attempting to fertilize an egg (1). Precum can also help with lubrication on insertion.
Precum is made up of mostly common nutrients and ingredients, with water being the #1 thing making up pre ejaculatory fluid. Being that water is the #1 ingredient, drinking more water is the best thing you can do! This goes for both making more semen, and for making more precum. Giving your body the liquid it needs will help you produce more liquids, like precum.
Aside from drinking enough water, there are vitamins and supplements you can take to increase precum volume as well as semen volume.
First let's take a look at what's in the Holy Grail of Cum stack. It's as follows:
These dietary supplements have been proven to do various things, including improving prostate health, reducing risk of BPH, promoting sperm health, and more. Another advantage of taking these supplements together is, in combination with increased fluid intake, they have shown to increase semen volume. Since precum is essentially semen without sperm in it, yes, it can increase precum volume.
Precum is made mostly of water and mucus. It is generally not as thick as semen. It contains around 20 calories, and is made up of small amounts of essential nutrients Among those nutrients:
These are all pretty standard nutrients, so if you're concerned with eating precum, don't worry! It's safe.
✔️ References
1. https://www.webmd.com/sex-relationships/how-many-nutrients-are-in-semen