Your wealth will go up if your effective rate after taxes is less than the inflation rate. That is, if your interest rate is R and marginal tax rate is T, then you need R*(1-T) to be less than inflation to make a loan worth it. Lately inflation has been bouncing around between 1% and 1.8%. Let's assume a 25% tax rate. Is your interest rate lower than between 1.3% and 2.4%? If not, don't take out a loan.
Another thing to consider: when you take out a loan you have to do a ton of extra stuff to make the lender happy (inspections, appraisals, origination charges, escrow, etc.). These really add up and are part of the closing costs as well as the time/trouble of buying a house. I recently bought my house using 100% cash. It was 2 weeks between when I agreed to a price to when the deal was sealed and my realtor said I probably saved about $10,000 in closing costs. I think she was exaggerating, but it was a lot of time and money I saved. My final closing costs were in the hundredsonly a few hundred, not thousands, of dollars.
TL;DR: Loans are for suckers. Avoid if possible.