Rye grains are known have a low GI rating. Meaning that eating a rye bread sandwich during your busy day can have great effects on your energy levels. This works by releasing glucose slowly into your blood stream .
Rye bread is much darker than other flours. When baking with rye often you will have a dark brown bread, adding seeds is a must when making your own bread. Seeds much like; sunflower, pumpkin , poppy, lax or sesame seeds go great with this bread.
Most commonly eaten in German sandwich, rye bread is famous and more commonly know as pumpernickel. You can find this bread in most German stores like Aldi and lidl.
Rye grains can help with snacking control. They have a high level of molecules which can help and contain water binding capacity. Normally the grains swell in your stomach and soak up the emptiness making you feel fuller for longer.
Always check the ingredients of your bread, often companies will use a colouring to make your bread look healthier than it really is. Food dyes like gravy browning are often added to the dough to make brown bread more brown. Look for over 50% whole grain content in your breads.
For more information on rye bread please follow; http://en.wikipedia.org/wiki/Rye_bread