A person's diet can affect how severely they experience premenstrual syndrome (PMS), with some foods making symptoms worse and others providing relief. For example, people who eat a lot of salt before their period may retain more water and experience bloating, while those who eat sugary foods may experience mood swings. There is some evidence that certain nutrients, such as Calcium and vitamin B6, can help reduce PMS symptoms. So, eating a balanced diet that includes these nutrients may be beneficial.