When you think of scuba diving, one of two things probably comes to mind: the thrill of checking off a bucket list adventure, or the cautionary tales about divers surfacing too fast and getting “the bends.” 

Either way, there are likely plenty of questions swimming around your head. How deep can you actually dive? How does your body adjust to being underwater? And what are the real risks you should know about? 

We’re here to dive into the answers to all your burning scuba diving FAQs. 

How Deep Can a Scuba Diver Go? 

Just how far you can venture into the ocean’s depths (or that cenote, quarry or lake you’ve been eyeing) depends on a few key factors, like your diving experience and the environment itself. For most recreational scuba divers, the safe limit is around 130 feet (or 40 meters). 

However, some divers go well beyond that. Welcome to the world of technical diving: a more advanced form of scuba that takes you deeper into caves, shipwrecks and other underwater landscapes. Technical divers rely on specialized gas mixtures with specific concentrations of oxygen, nitrogen and helium, carefully calibrated to match the dive’s depth and duration. With this specialized gear and training, they can safely reach depths of up to 330 feet (or 100 meters). 

What Happens to Your Body When You Scuba Dive? 

With the right equipment, you can dive deep enough to explore endless underwater oases and shipwrecks. But what exactly happens inside your body as you go deeper and return to the surface? Let’s break it down: 

• Immersion
  As you dive, the pressure pushes blood from your legs to your chest. This makes your heart work harder and can raise your blood pressure. You might notice a heaviness in your chest the deeper you go.

• Pressure
  Have you ever swum to the bottom of a deep pool and felt discomfort in your ears? Now, imagine diving eight times deeper.  

The deeper you dive, the greater the pressure on your body. This increased pressure affects your sinuses, ears and lungs, which may cause pain and an inability to breathe deeply. Blood flow to your brain also increases, which can intensify sensations of tightness or pressure throughout your body. 

• Cold
  The deeper you go, the colder the water becomes. As you descend into the cooler water, your blood vessels constrict, causing your heart to work harder to pump blood through them. This increase in pressure can make your body feel cold and stiff. 

How Does the Human Body Adapt to Diving? 

They rely on the mammalian dive reflex, a natural response seen in all mammals when submerged in water. This reflex kicks in immediately when divers go underwater and hold their breath. It helps conserve oxygen by slowing the heart rate and constricting blood vessels. 

The body responds with bradycardia (slower heart rate), apnea (a temporary pause in breathing) and increased blood vessel resistance. This effectively slows the heart’s beats per minute and redirects blood to vital organs, conserving oxygen for essential muscles. 

But it’s not all automatic: Divers also train their bodies to adapt to deeper dives and the increased pressure on their lungs. Through specific breathing exercises and lung training techniques, they can improve their oxygen efficiency and increase lung capacity, allowing them to dive deeper and stay submerged for longer. 

What Are the Risks of Scuba Diving? 

As with any adventure sport, there are risks involved when scuba diving. As mentioned earlier, divers can get decompression sickness (the bends) or other conditions related to increased pressure and gas absorption. 

Below, we explain some of the risks of scuba diving: 

• Decompression sickness
  This occurs when divers ascend too quickly, causing nitrogen bubbles to form in their tissues. Symptoms may include dizziness, joint pain and paralysis — and in severe cases, it can be fatal. The condition earned the nickname “the bends” because the intense bone and joint pain can cause affected divers to double over in excruciating pain.

• Barotrauma
  This injury happens when pressure differences between the inside of the body and the surrounding water cause damage. For example, sinus barotrauma occurs when unequal pressure affects the sinuses, leading to pain, nosebleeds or even facial swelling. Other forms of barotrauma may affect the lungs or ears. 

• Arterial air embolism
  This serious condition results from pulmonary barotrauma: when expanding air becomes trapped in the lungs during ascent. If air bubbles enter the arterial bloodstream, they can block blood flow to vital organs, potentially causing a stroke or heart attack. Divers can reduce the risk by breathing continuously and ascending slowly to avoid lung over-expansion. 

• Nitrogen Narcosis
  Divers who descend below 100 feet are at risk of nitrogen narcosis, where excess nitrogen under pressure affects the nervous system. This can impair judgment, coordination and decision-making, sometimes giving divers a sensation similar to intoxication. 

Explore the Depths of Health Sciences at the University of Florida 

Take your passion for health sciences to the next level with flexible online programs designed for working professionals. Whether you’re pursuing a career as a physician assistant, nurse practitioner or medical scientist, the University of Florida offers more than half a dozen online graduate credentials to help you advance toward your career goals. 

From a graduate certificate in medical anatomy and physiology to a master’s degree in medical physiology and pharmacology, you can customize your education to match your professional ambitions. And with fully online options, you’ll have the freedom to earn your graduate credential while balancing work and life — at a pace that fits your schedule. 

Browse our online programs and take the next step in your health sciences journey. 

Sources:
https://oceanexplorer.noaa.gov/technology/technical/technical.html
https://dan.org/health-medicine/health-resource/dive-medical-reference-books/the-heart-diving/basics-of-your-heart-circulatory-system/#affects
https://pubmed.ncbi.nlm.nih.gov/30855833/
https://pmc.ncbi.nlm.nih.gov/articles/PMC11168797
https://pmc.ncbi.nlm.nih.gov/articles/PMC7965165
https://www.ncbi.nlm.nih.gov/books/NBK470304 

You’ve seen it in movies: The main character, destined for college, shocks everyone by taking a year off to travel or pursue a passion before deciding their next move. But what about in the real world? How does a gap year play out for students who’ve just earned their undergraduate degrees and are contemplating medical school? 

A gap year — sometimes called a sabbatical year — is a chance to step back, explore new experiences and work toward personal or professional goals. The beauty of a gap year is that it’s entirely customizable. Some students take one after high school to gain clarity on their college plans, while aspiring medical students might use it to strengthen their med school applications. 

If you’re considering medical school, deciding whether to take a gap year is a big choice, with both benefits and drawbacks. Below, we break down the pros and cons to help you determine the best path forward. 

Gap Year Benefits 

Consider these advantages of taking a year to prepare for medical school. 

Enhance Your Application

From securing letters of recommendation to sending your transcripts, the medical school application process is a marathon, not a sprint. A gap year not only gives you time to assess your application for any potential weaknesses but also the opportunity to improve them. 

If you need to boost your GPA or MCAT scores, the University of Florida offers several graduate certificates that can deepen your understanding of medical sciences. What’s more, these certificates are offered entirely online, with all courses available asynchronously. This flexibility allows you to complete your coursework at your own pace, whether you’re traveling the world or interning at a healthcare facility to enhance your medical school application. 

Focus on Your Interviews and Volunteering

Congratulations — your medical school application has caught the attention of the admissions team, and they want to schedule an interview! This crucial step gives you your first chance to make a personal impression, but it’s more than just answering tough questions. 

With a gap year, you’ll have the freedom to plan your travel arrangements without the pressure of exams or assignments looming. Picture this: you fly to another city for your interview, only to come home and immediately face an important exam. A gap year gives you the flexibility to manage your interview schedule and even explore new cities, all while reducing stress. 

Additionally, during your gap year, you’ll have more time to volunteer. Not only will this strengthen your application, it will also give you the opportunity to personalize your interview responses with real-world experiences and insights. 

Gap Year Disadvantages 

While a gap year offers numerous benefits, it’s important to consider the potential drawbacks as well. 

The Cost Factor 

While a gap year offers valuable personal and professional growth, it also comes with financial considerations. College expenses are typically covered by scholarships, grants or student loans, but taking a gap year could affect your student loan repayment schedule. Many lenders offer varying deferment policies, so it’s crucial to understand your lender’s terms — especially if you plan on attending medical school afterward, as there may be exceptions for students in this path. 

Another financial factor to consider is the opportunity cost of missing out on a year of a physician’s salary. This delay in entering the workforce can add to your financial burden, making it more challenging to repay student loans or cover other expenses. 

Readjusting to Life as a Student 

As a child, were you one of those students who could easily slip back into “student” mode as soon as the school bell rang on the first day of class? Or did you find yourself dragging your feet as you retrained your brain to focus? If you struggled to adjust back to the pace of school after summer break, a gap year might make the transition to medical school more challenging, as the coursework is more intense and the time away is longer. Applying to medical school during your junior year allows you to maintain your academic momentum and avoid the adjustment period that comes with taking time off. 

There’s no right or wrong answer when it comes to taking a gap year – just what’s best for your personal situation. Regardless of your decision, our online graduate certificate programs are available year round. Get started and submit your application today! 

You’ve heard the saying “an apple a day keeps the doctor away.” But what about nature’s other daily remedy, sunlight? 

While there may not be a catchy phrase for it, regular, moderate sun exposure plays an important role in supporting your immune system. From vitamin D production to stimulating immune cell activity, the sun can do more than just boost your mood (or your tan). 

Of course, all things in moderation, sunlight included. Too much sun can suppress immune function and increase your risk for serious conditions, including skin cancer. 

In this article, we’ll break down how sunlight affects your immune system: the benefits, the risks and what future healthcare providers should know about finding the right balance. 

How UVA and UVB Rays Affect Your Skin and Immune System 

Before diving into the benefits and risks of sun exposure, let’s look at what happens when UV rays hit your skin. Sunlight delivers energy in the form of ultraviolet (UV) radiation, which triggers several biological responses. 

There are two main types of UV rays that impact human health: 

• Ultraviolet A (UVA)
  These rays penetrate deeper into the skin and make up about 95% of the UV radiation that reaches Earth. UVA is responsible for tanning and also contributes to skin aging and wrinkle formation. It can also damage cells by generating free radicals, the unstable molecules that harm DNA, proteins and cell membranes. 

• Ultraviolet B (UVB)
  UVB rays affect the outermost layer of skin, the epidermis. They’re the main cause of sunburn and can lead to long-term issues like skin cancer. On the positive side, UVB rays also trigger vitamin D production in the skin, a process essential for immune support. 

Vitamin D and Immune System Health: The Sunshine Connection 

Fun fact: Your body can’t make vitamin D on its own. It relies on outside sources, and one of the most natural forms is sun exposure. 

So, how do UVB rays help your body make vitamin D? The infographic below illustrates how sunlight transforms to active vitamin D: 

Once converted into its active form, vitamin D plays a crucial role in immune function. It binds to vitamin D receptors in immune cells and helps the immune system in several ways, including: 

• Enhancing the body’s first-line defenses (the innate immune system). 
• Regulating and calming the second line of defense (the adaptive immune system). 
• Reducing the risk of some inflammatory and autoimmune diseases. 

Surprising Benefits of Sun Exposure for Your Immune System 

Vitamin D synthesis is a well-known benefit of sunlight, but recent studies show sunlight can also enhance your immune function in other ways, including: 

• Stimulating antimicrobial peptide production
  UVB rays also trigger the production of antimicrobial peptides (AMPs), natural proteins that help neutralize pathogens like viruses and bacteria. These peptides boost the innate immune response by recruiting immune cells to sites of injury and helping wounds heal.

• Enhancing T cell activation with blue light
  While the sun may appear yellow or orange, daylight actually contains a full spectrum of colors, including blue light. Blue light helps regulate your circadian rhythm and, according to a 2016 study, may also help T cells (crucial immune cells) respond more quickly to threats. 

What Are the Effects of Too Much Sun Exposure? 

Sure, a little fun in the sun can support your tanning efforts and give your immune system a boost, but too much of a good thing can backfire. Excessive sun exposure can produce the opposite effect: 

• Suppressing immune function
  In the short term, too much UVA and UVB can lower your skin’s ability to trigger its innate immune response. Prolonged exposure, however, may raise your risk of infections and reduce your body’s ability to detect and fight cancer cells. 

• Damaging cells
  Prolonged exposure to UVA and UVB rays can cause DNA mutations, increase inflammation, speed up signs of aging and raise your risk for all types of skin cancer. 

Sunlight and Autoimmune Disease: What the Research Shows 

Sunlight plays a complex role in autoimmune conditions, offering both potential benefits and risks: 

Multiple Sclerosis (MS) 

Epidemiological studies suggest that increased sun exposure, particularly during childhood and adolescence, may reduce the risk of developing MS. This protective effect is likely tied to sunlight’s ability to regulate the immune system.  

Systemic Lupus Erythematosus 

Conversely, for people with lupus, sun exposure can worsen symptoms. UV radiation may trigger skin inflammation and systemic flares, including kidney issues, by activating immune responses that increase inflammation.  

Safe Sun Exposure Tips for Immune Support 

The sun is unavoidable — and that’s a good thing! Besides prompting vitamin D production and supporting your immune response, it can also improve your mood, help you sleep better and keep your bones in tip-top shape. 

So, what’s the sweet spot when it comes to sun exposure? 

Aim for 10 to 30 minutes of sunlight per day, depending on several factors: 

• Your skin tone
  Darker skin tones need more sun exposure to produce adequate vitamin D compared to lighter skin tones. 

• Your location
  The closer you are to the equator, the more direct sunlight you’ll receive year-round. 

• The time of year
  During winter months or cloudy weather, your body may need more exposure to achieve the same benefits. 

Here are some other tips for safe sun exposure to use when planning your next outdoor activity: 

• Use a broad-spectrum sunscreen
  For long-term protection, opt for sunscreen with at least SPF 30 that shields against both UVA and UVB rays. Reapply every two hours, or more frequently if you’re swimming or sweating. 

• Seek shade during peak hours
  UV radiation is strongest between 10 a.m. and 4 p.m. During this time, find shelter under trees, umbrellas or canopies whenever possible. 

• Wear protective clothing
  Hats, UPF clothing or regular clothes that cover your skin help block direct sun and reduce your risk of sun damage. 

Study Human Physiology and Immune Response with UF’s Medical Physiology Programs 

Understanding the complex relationship between sunlight, the immune system and overall health is just the beginning. UF’s online graduate programs in medical sciences offer a flexible, in-depth path to explore these topics and more.  

Whether you’re pursuing a career as a physician, physical therapist or another health sciences role, our programs are designed with working professionals in mind. Fully online and taught by expert faculty, our programs support your goals without disrupting your schedule. 

Explore our online program options to find the right fit for your career path. If you have questions about tuition, start dates or anything else, we’re here to help. We look forward to welcoming you to Gator Nation! 

Other articles you may be interested in:
How Does the Immune System Work? 3 Key Strategies
The Aging Process: How and Why We Age 

Sources:
https://www.mdanderson.org/publications/focused-on-health/what-s-the-difference-between-uva-and-uvb-rays-.h15-1592991.html
https://pmc.ncbi.nlm.nih.gov/articles/PMC3166406/
https://dermnetnz.org/topics/antimicrobial-peptides