Nightshades have been implicated in joint pain for actually encouraging the OVER absorption of calcium in your body. They have a lot of calcitriol in them which can lead to over absorption of calcium in the body by bypassing the natural way your body deals with calcium intake. The calcium then gets deposited in joints and tissue.

Nightshades also have solanine and a few related compounds which in upper limits are potent poisons. Its why you don't eat green potatoes and such. However if you are sensitive to the compound it causes muscle stiffness which you might have when you get up in the morning.

Then there is Capsaicin which is found in peppers. It's been claimed to be a boon for anti-cancer properties but its also been shown to slow healing in joints.

Switching to paleo means you probably eat more vegetables than you did before and perhaps that might involve too many nighshades?

Nightshades include... Tomatoes, potatoes (but not sweet potatoes or yams), eggplant and peppers (all peppers like chili peppers, habenero, cayenne pepper and paprika but not peppercorns like in black pepper, that's fine). Some 'berries' are nightshades too, like goji berries.

Weston A. Price Foundation says to avoid all nightshades for 6 weeks and see if your pain/stiffness goes away. If you can't tell they say after six weeks go on a nightshade binge for 2 days and see if the old symptoms come back with a vengeance. Here is a link to their article http://www.westonaprice.org/food-features/1897-nightshades.html

There are a lot of things that can cause achy joints. Vitamin D deficiency is a very common one. Are you getting your sun dosage often? You could also be laking in B-12 or vitamin C. Sometimes, the problem might even be a virus.

On the flip side, the fat soluble vitamins can build up in the body, especially if you are taking supplements, and overconsumption is said to have side effects like achy joints. Probs can occur from too much VITAMIN A, VITAMIN D, VITAMIN E and VITAMIN K. D will probably only be in excess if supplemented as the body can regulate D production from the sun. And for instance, fresh spinach greens have tons of K so I no longer eat those every day, just in case (although I never had any physical symptoms). I have a tendency to eat the same things over and over so I have to remind myself to get variety. You might also look into the balance between the vitamins. You might be over consuming some and underconsuming others and they may need to be eaten in a more balanced way. And look into any supplements you may be taking. If you eat a lot more healthy food, then sups that may have once been useful may now be too much.

Ironically, fatty acid deficiency can also cause achy joints. This is becoming more common as many people attempt to cut out saturated fat in a misguided attempt to be healthier. Luckily, this is unlikely to be a problem for paleo eaters.

However, looks like calcium defiency symptoms often involve muscle cramps and spasms and dry skin and nails and achy joints do not seem to be a common symptom of Calcium deficiency.

I tend to tell everyone the same thing and that is go to a free site like fitday.com and plug in your food intake info and it will give you a break down of your nutrient consumption each day. Then you can see if you are over or underconsuming any nutrients to any large extent. -Eva

It's quite interesting, that I had really bad knee pains when I started working out, and my rheumatologist said, that b/c I have a fibromyalgia I should basically suck it up. The pain was not only during the workout, but also became chronic.

Lo and behold - just weeks after I started to eat meat, fat and cut on grains the pain stopped, I could work out again (I had a break for a few months) and even do squats and lounges without any problem.

I do not take any supplements... I figured I would wait more months of proper eating and then maybe ... now I've been over 6mo and am waiting for my blood work so I can decide what do I really need.

I think in my case it must have been upped protein and fat intake. Cutting carbs of course was important as well, but I think secondary.

Can you make some bloodwork?

How much fish oil are you taking? I had angry joints and what not and was taking fish oil, but then realized my dosage was WAY too low and I needed to take way more.

This is a great site for figuring out home much you should be taking http://whole9life.com/fish-oil/

You a Crossfitter? If you are it might simply be your body getting used to years of imbalanced muscle training and now building muscle the right way.

Check your PH level. to much acid and your joints wont heal because of inflamation.