Couples routinely keep secrets from each other despite the damage this does to their relationships. These secrets can range from innocent mistakes to more serious lies.

Relationships secrets can vary, but there are some common trends among them.

If you suspect your loved one isn't being upfront about everything, one of these secrets might be the culprit:

1. Money secrets

One of the most common secrets in relationships is money and tends to be focused on spending.

Most couples don't hide their salaries from each other. However, they often hide how much they spend. From an innocent fib about finding something on sale instead of paying full price to more serious lies about thousands in credit card debt, the secrets can differ.

Both men and women try to hide their spending habits.

2. Food secrets

This secret isn't always easy to keep in a relationship since you usually share a kitchen. It's not hard to spot the candy wrappers in the trash can or notice the extra bottles of soda in the fridge.

Couples still manage to keep food secrets from each other. However, they're usually related to eating out instead of what they eat at home.

Couples sometimes try to hide what they had at a fast food place or a restaurant by sneaking them in the car or at work.

Most of the food secrets happen when one or both partners are supposed to be on a diet. It's tempting to cheat, and it's easy to pick up food as you do errands or return from work.

3. Cheating secrets

Infidelity is a serious issue for many relationships.

Your partner will probably try to hide that he or she is cheating on you. It's rare for them to blatantly parade another person in front of you or to discuss their affairs while you're still in a relationship.

Cheating secrets are some of the most damaging to the security and long-term success of a relationship.

4. Exercise secrets

Some couples will hide how little they exercise, and some will try to hide how much they exercise.

Although it's more common to keep secrets about not working out, there are cases of people lying about working out more. Some of these are related to eating disorders, and your partner may be keeping the high workouts a secret because they want to burn off too many calories.

5. Television secrets

This secret may seem unusual, but it's more common than you think.

Some couples keep their television habits and favorites a secret from each other at home.

In many cases, they have an agreement to watch a show together, but one of them will cheat and watch it alone. Then, they try to keep it a secret and pretend they haven't seen the latest episode.

In other cases, partners are embarrassed to watch trashy shows or bad comedies. They may keep their TV habits a secret because of shame or guilt.

6. Secrets about their “ex.”

Often, couples will keep meetings or phone calls from a former partner a secret.

Most couples worry about their loved one finding out an ex is back in their lives. They don't want to sabotage the new relationship, so they hide it.

Secrets can hurt both people in a relationship, and the damage can extend to other members of their families.

Although you know you should be honest with your partner, it's not always easy, and secrets are sometimes hard to avoid. In most cases, though, honesty is the best policy. Honesty naturally builds trust and strengthens your relationship.