From my research nail issues can commonly show up with increased stress (emotional or physical- crossfit anyone? ;), sickness or malabsorption of nutrients. While Paleo is awesome, we are all different and have different digestive 'situations', lives and relative nutrient needs. You may need to change up your diet a bit to include a few of the key components your body is currently in need of.

I've had increasing vertical ridges in my nails for years- it wasn't until after I was diagnosed Celiac that I did the research that indicated that mine were most likely due to nutrient malabsorption, particularly the B vitamins ( especially B12) and potentially iron.

In the last 6 months I've done several things (in addition to going Paleo) that I credit with helping greatly reduce the ridges...

• B vitamin shots 1- 2x per month. I get the B12, B1, B6 and folate combo... Often these will be offered at a local community health store.
• sublingual B vitamins for better absorption- Sprouts has one with B12, B6 and folate.
• digestive enzymes and HCL with each meal to increase nutrient/mineral absorption
• probiotics- both transient ones like lacto and bifidio strains and some of the the longer term colonizers (Prescript-assist or Bio-Kult have some). Note: most supplements only have the transient species which are great helpers, but only stick with you for about a week before heading out. These bacteria help us by producing a constant stream of vitamin k and b vitamins. Nice lil guys...
• prebiotic & probiotic 'living' foods like sauerkraut, kombucha, kefir...
• reduced physical and emotional stress- including cutting back on my excessive workout schedule.

From what I've read it can take a while to get back to smooth nails- anywhere from months to years depending on the severity of your case. Mine are already greatly improved, especially after the regular B vitamin shots. Hope this helps.

NOTE: I have seen multiple doctors that assured me that the ridges were common and 'no big deal' (they said that about my initial celiac symptoms as well) , but their resolution after going gluten free and adding some key nutrients makes it seem likely to me that they are indicative of some low to moderate level of malabsorption. Probably not a HUGE worry, but something to pay attention to.

Here are a few quick links for general overview, unfortunately I don't have time to look up any pubmed goodies' so these will have to do ;)

http://www.askanaturopath.com.au/faqs/ridges-on-nails/p/403

http://www.wisegeek.com/what-causes-ridges-on-fingernails.htm

http://www.pamelaegan.com/articles/fingernails.htm

Note: I've also seen vertical ridges mentioned in rare cases as a result of kidney issues- probably not the case for you, but always good to know.

I have that too, well before I started eating whole foods. My nail will split at the ridge, so I tend to keep them very short. For a long time I only had one ridge on one nail, but I am starting to get them on other nails. It would be great if anyone knew what they were; calcium deficiency?

Sounds like lichen planus. Nothing to do with Paleo

I have the same thing. I've had it for a long time -- years and years -- and found no difference on Paleo. I looked it up a couple of months ago and everything I read basically said it's nothing. Or it didn't fit any of the illnesses, deficiencies listed for nails.

I have it too. Deep ridging may indicate problems, but superficial ones are pretty common. Hypothyroid keeps coming up as a potential link. I dunno, I guess if it wasn't so common the manicure section of the store wouldn't sell so many of those buffer thingys (clearly I do my nails a lot - I have no idea what that thing is called).

I have them too. I first noticed them at about age 52 or so. Had nothing to do with paleo as I wasn't eating paleo at that time. Nobody mentioned age when they first noticed them but I have read that it is more an age related condition. I seems most age related conditions are related to high refined carbohydrate consumption during an individuals lifetime.

I also use a buffing block to smooth my nails.

I have them, and because it gets worse when I pick at my cuticles more I have always assumed it was because I abuse my cuticles.

I don't think it's age. I think it's from a bad diet. The age thing has to due with having a bad diet for long periods of time that it ruins the digestive system and begins to show up on your nails. I began to get ridges and indentations on my nails when I was 7. My family noticed it before me. I wasn't concerned. We saw a specialist of some kind who told my parents I needed to take vitamins, but I was never good at that. I always suffered from some mild digestive issue until I turned 21 and then all hell broke loose. For the past 5 years I've struggled to regain a normal existence. I'd suggest taking these little hints from our bodies seriously. You don't want to increase your deficiencies and gain even more health problems.