It’s no marketing secret that social media has become big business. Companies have discovered that it can be more cost effective for marketing of their big brands than traditional advertising because of its ability to reach large audiences. But what about its use by companies in heavily regulated industries?

Industries that market pharmaceuticals, health care, financial services, insurance, alcohol and tobacco or that serve government entities must follow strict guidelines and regulations. For example, medical organizations are required to abide by rules like keeping a patient's medical records confidential and federal departments and agencies must ensure that their websites comply with Section 508 and are accessible to people with disabilities.

The conventions of social media make following such rules difficult at times. Not only are people willing and accustomed to disclosing personal details about themselves on social media, outlining warnings and safety information can be a challenge on a format like Twitter's, which allows for just 140 characters.

Related: Writing Social Media Guidelines for Your Company? Tread Carefully.

That doesn’t mean that companies whose services are regulated should avoid social-media platforms. Social media is a great resource for sharing and discussing valuable information. When done effectively and legally, social media can assist any entity in one of these regulated fields. Here are four ways that regulated companies can use social media:

1. Sharing industry information. Even firms strictly regulated by state or federal governments can use social media to make announcements or even share vital information with potential or current customers.

Health-care companies could take to social media to share the dangers surrounding a new weight-loss pill or facts about the Affordable Care Act. But social media use doesn’t have to be just serious. The United States Department of Agriculture has taken advantage of National Hot Dog Day to share everything people might want to know about the frankfurter in a lighthearted way.

Another way to share information is to direct Facebook or Twitter users to a landing page where they can learn more information, sign up for a newsletter or even interact with employees. 

Consumers Energy uses social media to provide updates if there is a power outage. 

2. Allowing customers to exchange information. Social media offers an easy way for people who don't know one another to exchange information: Parents of children with a serious medical condition can share their experiences, offer advice or even learn more about the illness involved. In this same vein, legal or financial firms might want to offer factual information on their social-media pages as an alternative to what's offered on overtly partisan websites.  

Related: The Esquire Guy on Handling a PR Crisis With Style

3. Listening to social media chatter. With the increasing amount of online conversations taking place, social-media platforms are great resources for discovering what is being said about a brand, industry or service or their competitors. If many customers had a terrible experience with a financial institution, that company might be wise to pay attention to complaints on Facebook or Twitter to better address and correct them.

Some companies choose to archive social media conversations, which is required for legal purposes. This way companies can retain a historic perspective about particular topics discussed. This also allows them to monitor and analyze which marketing campaigns worked, how people perceived their brand or when and why individuals discussed their brand on social media. These insights can offer more in-depth and unique information than what's found in surveys or focus groups.

4. Building trust. With the convenience and popularity of social media outlets, some consumers tap them to broadcast an unmet concern. When some financial firms monitor social media, they enlist a real staffer to send private messages instead of sending an automated or scripted response. That can build trust and comfort a customer that the matter in question -- such as difficulty logging on to the company's website -- will be handled in a reasonable amount of time. 

Do you have things can't say on social media in your regulated field? I'd love to hear in your comments below.

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