Every time the Forbes 30 under 30 list comes out, it sends a chill through the ancient souls who have lived past that terrifying birthday. Never made the list? Too late, friend. Now, please never think about it again.

When we have a "milestone" birthday, it's a chance to reflect on where life has led us and to think about some of the lessons learned along the way in order to make the next decade better than the one before. I turned 50 earlier this year. My 40s were a very challenging period in my life but I've learned a lot about myself in that time. Here are some of the lessons I've learned.

Android/iOS: Sunscreen isn’t just for preventing sunburns. The sun’s rays are responsible for much of the wrinkling, thickening and brownish spots that show up over time, especially on light skin. Fortunately, a good broad-spectrum sunscreen will protect you, and this app simulates exactly how much.

I grew up a sedentary nerd, resenting PE and failing miserably at the few sports I tried. But in my twenties I found some forms of exercise I didn’t hate, and in my thirties I started using the word “athlete” to describe myself.

If you had to guess what the best era of a life would be, you might say being young and without responsibilities or old with a retirement fund. It turns out that for a lot of people, the best part of their life is the slog of middle-age.

Fresh lime juice is a key component to many fine beverages, and it's always been my understanding that you want it as fresh as you can get it. This thinking, it turns out, was folly. For the best tasting beverage, you want to let your juice age for a little bit - ideally four to 10 hours.

I know what you're thinking, and I agree, so let's just get this out of the way: "Having someone to take care of you when you get old" is a terrible reason to bear children. But since you may currently be in the trenches of wiping the bottom of a person who keeps calling you Squishy Belly Mummy and wondering, "So when is this whole parenting thing supposed to pay off again," let's look at some numbers, shall we?

Another year and we're another year older. But the inevitable march of time has a bright side -- we're all getting older, and older people have higher emotional well-being than teenagers and young adults. Our happiest days don't have to be behind us.

If you're a person with a uterus, you probably got an awkward talk when you were around nine or 10 explaining some changes that were coming for your body. (Maybe you saw a movie that memorably involved pancake batter poured into the shape of the female reproductive system.)

Call it the new game of Truth. Players go around the table answering questions in their little blue booklets, but these questions aren't geared to get them talking about that one time they went skinny dipping in Bali. Instead, the questions aim to launch difficult conversations, ones that may be painful, ones they may have been avoiding for far too long.