Ah, youth. You think you can get by forever on less sleep, indulging when it comes to food and alcohol, and multi-tasking your way through endless lists -- but that fountain doesn't flow forever.

"Once you turn 40 it's not so much so," said natural health expert Dr. Christine Horner. "It's important to start paying attention because [if you don't] it's something that can lead to significant health problems."

Dr. Horner explained that women over 40 make four big mistakes:

1. Neglecting Heart Health

"Sugar actually is the thing that really accelerates every kind of disease including heart disease," she said.

Ditch the junk food and processed food and replace it with fresh fruits and vegetables. Take fish oil or krill oil supplements and take time to relieve stress with yoga, meditation or Tai Chi.

"What it does is it trains your nervous system to not respond quite as strongly as it normally would," Horner said.

2. Mismanaging Menopause

Rather than going for pharmaceuticals or hormone replacement therapy, Dr. Horner recommended safe, plant-based remedies to quiet dreaded side-effects like hot flashes, mood swings, night sweats, dryness, and sleep disturbances.

"There are really effective choices," said Horner. "Relizen is from Sweden, and it's made from yellow daisies. There's maca from South America; it's considered a super food used for energy and libido. But they also found it helps to balance hormones. Black cohosh-- the Native Americans use that, and then flaxseed."

3. Accepting Weight Gain

"There's a huge mental component," said Dr. Horner. "What we think of as aging and accepting, 'I'm going to slow down, I'll get heavier, and I'll get aches and pains, that's just hoo-ha,'" Horner said.

If you're not into the gym, use the stairs at work, park far when you go shopping, or just walk for 30 minutes per day.

"Exercise is super important and the amazing thing is -- you don't have to do very much to have a huge impact," Horner said.

4. Failure to Love Yourself

"We have this little committee inside our head that's constantly criticizing us," Dr. Horner said. "When you have negative emotions like that, these molecules will actually hook onto your immune system, your DNA -- and it will weaken your immune system and activate genes for poor health."

Practice self love by treating yourself like you would treat your best friend. Buy yourself flowers. Carve out time for a spa day and do something just for you every day.

The #1 emotion associated with good health: Love and support!