Nightshade Vegetables and Bone Health

, the nightshades, horsenettles and relatives, is a large and diverse genus of annual and perennial plants. Most parts of the plants, especially the green parts and unripe fruit, are poisonous to humans (although not necessarily to other animals), but many species in the genus bear some edible parts, such as fruits, leaves, or tubers. Food members of the nightshade family include:
  • Bell Peppers
  • Chile peppers (not black peppers)
  • Eggplant
  • Potato (not sweet potatoes)
  • Tobacco
  • Tomato
In a few studies, plants in the nightshade family, Solanaceae, have been found to cause pain and swelling in a small population of subjects with degenerative arthritis.[6]

Bad to Bone Health?

According to Dr. Norman Childers[1], nightshade consumption correlates with osteoarthritis because these plants contain glycoalkaloids, which disturb calcium metabolism and tend to remove calcium from  the bones, causing aches, pains, and even deformation.  Dr. Childers has found that when people with osteoarthritis, joint pain, bursitis, and bone spurs stop using these foods, in many cases their pain and symptoms abate dramatically after four to six months.

Glycoalkaloids are generally poisonous.  For example, we find them as nicotine in tobacco, solanine in potato and eggplant, and tomatine in tomatoes.  They may also have stimulant properties, as capsaicin (in chile peppers) does.  A number of drugs are made from nightshade plants,  including scopolamine, atropine, hyoscyamine (Symax), and belladonna[2].

Nightshade vegetables are believed to affect calcium balance .  Dr. Annemarie Colbin has theorized that people eat nightshades to counterbalance their consumption of milk products, which have more calcium than human beings need.  She has noticed that in a dietary system high in dairy, people commonly also eat plenty of nightshades, in classic combinations such as pizza, eggplant parmigiana, potatoes and sour cream, curries and yogurt, and so on.  She believe that the nightshades might help in breaking up or neutralizing the excess calcium.

Theoretically, she believes, dairy and nightshades are opposite and complementary: If you eat one, you need the other.  Conversely, if you stop eating one (say, dairy) you might do well to abandon the other, or there may be repercussions on your body's calcium balance.  

Each Person Is Unique

Dr. Annemarie Colbin has noticed that some people have found  that if they keep eating nightshades after adopting a low-fat, dairy-free diet, their joints begin to ache.  However, she also has found that some people are very good at balancing milk products and nightshades.  They don't seem to react to either, remaining free of arthritis, joint pains, bone spurs, and other problems related to consumption of both nightshades and calcium.  Others are highly sensitive to these plants and feel pains in their joints as soon as they eat even a little.
In any case, Dr. Colbin has suggested, it may be sensible to pay attention to the food nightshades because of their ability to affect calcium balance.  For those at risk for osteoporosis or already suffering from osteoarthritis, it could be a good idea to refrain from relying heavily on these vegetables in the diet.

Photo Credit

  1. Childers, N.F. 1999.  Arthritis--Childers' Diet That Stops It!  The Nightshades, Ill Health, Aging, and Shorter Life.  Gainesville, FL: Dr. Norman F. childers Publications.
  2. Childers, N.F. 2002. Apparent relation of nithgshades (solanaceae) to Arthritis and Other Health Problems.  Journal of Applied Nutrition 52(1):2-10.
  3. The Whole-Food Guide to Strong Bones by Annemarie Colbin, Ph.D.
  4. Building Strong Bones (Travel and Health)
  5. Solanine Toxicity Syndrome
  6. The Immune System Recovery Plan by Susan Blum, M.D., M.P.H.
    • Avoid foods in the nightshade family because they can trigger arthritis symptoms.
  7. How to think about food: Annemarie Colbin at TEDxManhattan 2013