Sweet potatoes for lunch Why? Top 3 reasons ... 1. They are high in vitamin B6. Vitamin B6 helps reduce the chemical homocysteine in our bodies. Homocysteine has been linked with degenerative diseases, including heart attacks. 2. Sweet potatoes do not cause blood sugar spikes. Sweet potatoes are naturally sweet-tasting but their natural sugars are slowly released into the bloodstream, helping to ensure a balanced and regular source of energy, without the blood sugar spikes linked to fatigue and weight gain. 3. They are a good source of vitamin D, which helps build healthy bones. Vitamin D plays an important role in our energy levels, moods, and helps to build healthy bones, heart, nerves, skin, and teeth, and it supports the thyroid gland.