Energy levels are mostly dependent on the following factors: blood pressure, blood sugar, various hormone levels and levels of vitamins, such as vitamin B; and levels of various minerals, such as iron. Various energy providing foods and supplements work by addressing these issues. To avoid picking up weight or worsening some hormone levels, I advise having your health practitioner checking all of these to determine exactly where the problem is originating, before trying some high energy foods. Remember to take along all of the supplements and medications that you are currently taking for them to examine too.