For centuries, people from a variety of cultures worldwide have practiced fasting to promote physical or spiritual healing. Over the past few years, there’s been a renewed interest in fasting. Many people turn to fasting as an alternative to weight loss diets or as a complement to medical treatment for health conditions.

However, people with human immunodeficiency virus (HIV) must be cautious when making big changes to their diet or lifestyle. Before you start a long-term fast, think about your medication, how much you weigh, and any other health issues you might have. While you should always consult your health care provider for medical guidance, here’s some background on fasting with HIV.

Different Forms of Fasting

The term fasting can mean different things to different people. There are several ways to fast, and not all types of fasting affect the body in the same way. For example, during a water fast, you drink only water and don’t eat any food. A dry fast means you don’t eat food or drink water at all when you’re fasting.

Intermittent Fasting

The term intermittent fasting (IF) has gained traction in the health and fitness world. Also known as time-restricted eating, IF involves following a set schedule of feeding and fasting times. Water is allowed during the fast, but not food. Some versions also allow other beverages during fasting hours, like coffee or even diet sodas.

People may follow intermittent fasting every day by restricting their food intake to a set eating window. Popular varieties include 16/8 and 14/10. In 16/8, fasting happens for 16 hours (including through the night), and eating can happen anytime in the eight-hour window. Intermittent fasters can customize their eating schedule however they like, some choosing to eat earlier in the day (7 a.m. to 3 p.m.) or later (noon to 8 p.m.).

A stricter version of this is one meal a day, where the person eats one meal at a set time and fasts for the next 24 hours, such as only eating dinner at 6 p.m. with no meals or snacks in between.

Another type of intermittent fasting is the 5:2 method. On two days per week, calories are limited to 500 or less per day. The other five days are for a normal, healthy diet. Intermittent fasting may be tailored to the individual. Some people choose to follow a strict schedule, while others do it occasionally or vary their fasts.

Religious Fasting

Aside from intermittent fasting, many people practice a range of religious fasts. Common examples include the Lenten fast for Christians, which limits what you can eat and drink during the 40 days leading up to Easter. In addition, Muslims practice fasting for the month of Ramadan, where they consume food and water only during the evening hours between sunset and sunrise.

Intermittent Fasting for Chronic Diseases

As HIV treatment improves, people with the condition are living longer. That also means that they’re at risk for the chronic (long-term) diseases of aging. Excessive weight loss and muscle wasting are no longer as much of a concern for people with HIV as they were in the past. Now, obesity and associated conditions, like heart disease, high cholesterol, and diabetes, are more relevant for individuals with HIV.

Studies show that people living with HIV have more than double the risk of heart disease than the general population. Some of this higher risk is related to the side effects of having HIV and being on antiretroviral therapy (ART), a treatment using medicines to fight HIV. Nonetheless, obesity, high blood pressure, and high blood sugar are also potential contributing factors that may improve with healthy weight loss.

Research has found that IF has positive effects beyond the benefits that come from losing weight. For example, IF may lower inflammation and offer protective effects against diabetes, stroke, and heart disease compared to other weight loss approaches. However, some of this evidence is based on animal studies that may not translate to the same effects in humans, let alone those with HIV specifically. Until controlled clinical trials can show the benefits and safety of IF for people with HIV, it’s not clear if you can expect the same results. That’s why you should always talk to your doctor before trying any fasting diet.

Religious Fasting With HIV

Religious fasting is meant to benefit the spirit, but it can bring physical benefits as well. One study involving Muslims with HIV observed that those who fasted during Ramadan saw significant improvements in their blood work. This was compared to a control group, which is a set of people who didn’t fast or receive the treatment being tested, to provide a starting point for measuring the effects of fasting.

High-sensitivity C-reactive protein (hs-CRP) is a sign in your blood that shows there is inflammation and may show a higher risk of heart disease. During this study on HIV-positive participants on ART, hs-CRP levels decreased within two weeks of fasting for Ramadan, suggesting that this form of fasting is anti-inflammatory.

People with HIV need to consider the impact of religious fasting on the body before participating in a fast. Even if the physical effects aren’t the primary goal of the fast, they can still be significant and potentially dangerous for some. Because there’s such a wide range of religious fasting regimens, discussing the details with your health care provider will help you decide if it’s something you should consider doing.

Safety Considerations Before You Fast

Health care providers advise certain people to avoid fasting. For example, if you have diabetes and take insulin, fasting can require a change in your medication and careful monitoring to avoid potentially dangerous dips in blood sugar. Fasting also isn’t safe during pregnancy or for children and adolescents or people with a history of eating disorders.

Whether you’re thinking about fasting for health or religious reasons, it’s important to discuss your plans with your health care team. They may suggest ways to modify your fast to make it safer for you based on your health conditions and medications.

HIV Medication and Fasting

Members of myHIVteam have mixed feelings about fasting. One member shared, “I’m trying to lose some extra weight, and I’m looking into fasting. My issue is, can I take my meds during the fast, or should I avoid fasting altogether? Are there any benefits to fasting if you are HIV positive?” they asked.

Others responded with different opinions. One said, “Fasting isn’t a good idea. I’ve tried it before, and the results are temporary and screw with your general health. I think exercise and cutting back calorie intake is a better way. I lost about 85 pounds just by walking every day and watching what I eat.” Another member wrote, “I’ve done intermittent fasting and took my meds during the eating window.”

Not eating for a while can change how certain HIV drugs work in your body, which might affect their effectiveness. This is true for drugs like indinavir and didanosine.

Several HIV medications are better taken with food to prevent nausea and improve absorption. Some examples include:

• Atazanavir (Reyataz)
• Cobicistat (Tybost)
• Darunavir (Prezista)
• Dolutegravir and rilpivirine (Juluca)
• Etravirine (Intelence)
• Lamivudine and zidovudine (Combivir)
• Ritonavir (Norvir)

Fasting might be good for people living with HIV because it could help balance out the unwanted increase in blood fats like triglycerides and cholesterol that sometimes happen when taking HIV medications.

Although HIV doesn’t always prevent you from fasting, it’s important to bring up fasting with your doctor before making drastic changes on your own. You may need to adjust the timing of antiretroviral drugs or monitor for certain side effects.

Talk With Others Who Understand

On myHIVteam, the social network for people with HIV and their loved ones, more than 41,000 people with HIV come together to ask questions, give advice, and share their stories.

Have you considered religious or health-focused fasting? If so, did you need to adjust your antiretroviral treatment or other aspects of your medical care? Post your thoughts in the comments below, or start a conversation by sharing on your Activities page.