Some additional thoughts on when to take Social Security:
1. Much analysis indicates taking it at 62 versus 70 will keep you ahead financially until around 80 years of age (more or less depending on your investment assumptions AND factoring income tax implications and tax brackets). So, for the first 18 Years or so, you are ahead financially --> Do you think you really have another 18 years to offset the number of years you were ahead OR are you weighing those later years as much more in importance? Statistically, more than half of us will expire around our mid eighties.
2. Recent studies indicate that our spend rate actually goes down as we approach the later years of retirement - no more mortgage, no kids, no college costs, not as many 'toys' desired to purchase, not as much travelling, live in downsized homes, less utilities,... yes, large medical bills are looming for some of us.
3. Longevity tables may start showing, in a few years, that our predicted lifetimes will be decreasing somewhat. They have yet to fully factor in the current and next generation folks who have significantly jacked up the obesity percentages, lived sedentary lifestyles (many sitting 8 hours a day at work and spent hours sitting in front of a TV or PC), exercised minimally, ate processed foods with lots of 'chemical additives' with some that have been later removed, exposed to much more toxins in our water, air and food supplies than the people from earlier generations, continual exposure to low levels of RF radiation, possible effects from a lifetime of dental/fracture X-rays, airport scans and various other imaging technologies... Yes, the medical industry has made great strides in addressing many ills to help extend our lives, I'm just not convinced yet that it can undo everything that recent generations have been exposed to.
4. Waiting until 70 will give you the max payout, but will often also result in the max tax hit. Combine it with RMDs at that time, in addition to pension, dividends,... and the percent of taxable social security income could be significant versus taking it earlier.
5. Many are looking at the strategy of waiting until 70 as a guarantee 8% or so a year gain on their retirement assets. Is it an asset? If you have children, grandchildren, great grandchildren, a charity organization, church, cancer research, university... that you would like to leave a legacy to, your social security paycheck won't be going to either upon your death (OTOH, your surviving spouse who is dependent on your SS will benefit). The money you used while delaying your social security check could have been left to your beneficiaries. That money could have grown during the years you took early social security and you could have left the beneficiaries with a larger chunk of funds. Social security is more like an insurance based income stream that ends when you end.
There are tons of arguments for taking social security earlier and tons for taking it later. As been stated before, the best time is when it is right for your personal situation. Obviuosly, there are different considerations for the single individual versus the married.