One key, though, for those that have not yet adapted to eating a lot of fruit all at once is that unwanted blood sugar reactions can be due to adrenal gland weakness. Therefore, while fruit does contain sugar in its simplest and easily absorbed form (opinion based on the work of Dr. Robert Morse and my own effects with fruit on an empty stomach compared with other carb sources), some people may feel "wobbly" or otherwise not at there best when having any sugar source beyond a certain point.
If this were me, I would take adrenal supporting herbs/herbal formulas to hope to remedy the situation by strengthening the gland most responsible for sugar metabolism. Of course, the pancreas does deal with transporting sugar into cells but this is specifically glucose and fruit is more fructose-centered. Dr. Robert Morse has found that fruit may actually require less insulin than even vegetables (small amounts of glucose). This though, is not in any way a suggestion to stop taking insulin or any other doctor prescribed medication. That could be disastrous. Working with your doctor, if you are on medication, is key.
If you feel well with the fruit for breakfast approach, you may also want to try fruit for lunch. This can greatly accelerate hydration and detoxification as well as lightness of being and overall energy. This doesn't mean having a snack of fruit for a meal but having enough to feel satisfied and easily not hungry for other foods. Working up slowly may be necessary.
Fruit is amazing for cleansing and rejuvenating the kidneys and colon. These are two of the most important areas to heal in order to effectively release build up toxins which weigh down the body and spirit. Fruit can get that process in motion. By starting on fruit you continue the cleansing that went on during the 8 or so hours during sleep when various healing processes are underway.