Although some majors are "easier" than others, adcoms expect you to do well in the major that YOU picked. A nutrional science major who has a 4.0 will look better than a biochem major with a 3.5. There might be some forgiveness if there you're off by 0.1 grade points, but thats about it. Its one thing to want to challenge yourself, but challenges are meant to be overcome rather than cripple a person😉