If your last smoothie left your energy crashing an hour later, you might want to consider how some so-called healthy foods cause rapid glucose spikes. Nutritionists stress the importance of keeping blood sugar levels steady throughout the day. “If your blood sugar spikes too quickly, you can get a ‘sugar high,’ followed by a sugar crash, which can lead to fatigue, moodiness and cravings,” said registered dietitian nutritionist Chelsey Amer . It’s not always easy to balance, experts say. “