3 things that can derail your retirement savings

When considering the biggest regrets of 2014, most of us think of common year-end responses, such as what we ate and drank or spending too little time with loved ones. However, the growing American mass-affluent segment experienced the most guilt-for not investing enough for the future.

And while it may be surprising, according to our latest Merrill Edge Report, the sentiment correlates with what we found earlier this year: Americans' top fear is going broke in retirement. Put simply, Americans are seriously afraid of running out of money in their golden years, and they feel guilty about how they're handling it.

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Due to the changing retirement landscape and longer life expectancy, we're seeing more Americans take an introspective look at investing for retirement, benchmarking their progress and acknowledging their successes as well their shortfalls. Nearly 6 in 10 are setting a goal to save more for retirement this year, overshadowing losing weight, paying down debt and taking more trips. And while I'm thrilled to see this long-term focus and goal setting for 2015, our research tells us that many of us are facing some challenges.

So while investors seem to have good intentions, what is really prohibiting them from investing more year after year? In today's economy, here are three of the biggest challenges Americans are up against while attempting to build their retirement nest egg.

Student debt. Debt remains a prominent prohibitor to investing for retirement, particularly among those saddled with student loans. Student loans are now the second largest debt class, at $1.2 trillion, behind only mortgages, according to a recent study by Experian. With such staggering amounts of debt, we're seeing this greatly impact Americans, who are delaying investing for retirement in addition to prominent milestones until they've paid off this debt. This is particularly evident with the millennial generation.

Aging parents. As life expectancy grows and health-care costs rise, more middle-aged adults are playing an active role in their elderly parents' care. With many also financially supporting dependents of their own and nearing retirement age, this so-called sandwich generation is feeling significant financial pressures. Defined as people who are simultaneously caring for a minor or grown child, in addition to a parent age 65 or older, this generation fits the profile of approximately more than 4 in 10 Gen Xers and one-third of baby boomers, according to Pew Research.

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Everyday trade-offs and competing priorities. We continue to witness a trend of lifestyle preferences derailing financial goals, especially over the past two years. Most Americans are not convinced their short-term decisions really affect their finances in the long run, particularly what they spend on entertainment and eating out. Furthermore, future finances are clearly not top of mind. More than half respondents in our survey don't think about their long-term finances when making daily purchases.

These three challenges are extremely prevalent in today's world and are most likely some of the largest contributing factors to why more than half of respondents in our latest Merrill Edge Report did not save for retirement at all last year. So how can we start making good on our resolutions and start to put away more for retirement this year?

It can come from the simplest of actions-spending more time on budgets, seeking investment advice online to gain the confidence to make more informed decisions, and even implementing a monthly check-in to keep you accountable. If you don't know where to start, take the initiative to consult with a financial advisor.

Investing for retirement is a marathon, not a sprint. Small, steady strides are the key. So if you are facing one or all of these challenges, it's important to recognize the need to prioritize retirement and take actionable steps, investing as much as possible as early as possible. While Americans felt they could have done better with their finances in 2014, I am looking forward to more respondents feeling proud in 2015.

-By Aron Levine, head of Preferred Banking and Merrill Edge.