The one-milliliter-to-one-gram rule only works accurately for pure water at standard room temperature, or for liquids that share an almost identical density to water, such as clear broths, brewed tea, or distilled vinegar.
Every ingredient has a specific density, which is the ratio of its mass to its volume. When you treat every liquid or paste as having a 1:1 ratio, you run into discrepancies caused by these density differences. For instance, honey has a density of roughly 1.42 grams per milliliter. If a recipe calls for 100 grams of honey and you measure out 100 milliliters using volume markings, you end up with around 142 grams of honey, which easily explains why your chicken turned out significantly sweeter and heavier.
On the other end of the spectrum, culinary oils like olive oil or vegetable oil are lighter than water, with a density around 0.91 to 0.92 grams per milliliter. Dairy products like whole milk (around 1.03 g/ml) and heavy cream (around 0.99 g/ml) are close enough to water that a 1:1 approximation often works in forgiving savory recipes, but syrups, pastes, honey, and fats will noticeably skew your results.
If you prefer using your kitchen scale to save on clean-up, the best approach is to either look up the density conversion for heavier staples or use recipes specifically developed with weight measurements (grams). For everyday cooking, keeping a mental note that syrups and honey are roughly 40 percent denser than water will help you make quick, accurate adjustments on the fly.
