Chrononutrition and Nutritional Supplements: The Best Timing for Your Health

Have you ever taken a nutritional supplement like Vitamin B and thought it did not work well one day, then you took it at a different time another day and it helped? You felt more energized and ready for the day! Your body functions in the form of patterns known as circadian rhythms to promote sleep, eating, and other activities. It makes sense to time our nutrients based on our body’s needs and activities like a food clock. So when should I take them? Read on to find out how you can meet your nutritional needs and maximize your health in a timely manner!

What are nutritional supplements?1,2

The nutritional supplement market is expected to be worth over $151.85 billion by the end of 2021 and reach $272.44 billion by 2028. They really are popular among patients! Nutritional or dietary supplements are taken to supplement the diet of essential vitamins, minerals, and nutrients like amino acids and enzymes. They are not meant to replace your diet. Some are used to help you meet your dietary needs and manage health conditions while others promote weight loss or refuel you from sports. People with food allergies, vegetarians, pregnant women, and elderly may need supplements to make sure they reach their daily dietary goals. Nutritional supplements are commonly used in bone, heart, kidney, and cancer diseases. They come in a variety of forms from tablets to powders to drinks and bars.

How are they different from prescription and over-the-counter drugs?3

Both over-the-counter drugs and dietary supplements are available without a prescription and can be found along the aisles of your local drug store, unlike prescription drugs. Both have to follow good manufacturing practices (GMPs) to make sure their products are pure. Yet, they do not undergo the same regulations as prescription and over-the-counter drugs. They are still regulated by the Food and Drug Administration (FDA), but they do not have to be shown to be safe and effective before entering the market. Therefore, they are not drugs like prescription and over-the-counter drugs. All drugs have to be approved by the FDA prior to being sold at your local drug store and are used to treat diseases. Nutritional supplements are not meant to diagnose, cure, treat, or prevent any diseases. However, they can make health claims like “supports heart health,” but they can not state “treats hypertension.”

What is chrononutrition and when should I take them?4-6

Your body and its functions like sleeping, eating, body temperature, and immune regulations are completed like clockwork or circadian rhythms. Therefore, it makes sense to optimize these patterns by timing our diet too. This circadian diet or chrononutrition includes not only what you eat, but when you eat. You should eat when it aligns with your body’s activities like when you are more active or during the day instead of at night before you sleep. Your body functions better if you eat more earlier in the day than later, even though many people do the reverse. Research has shown that eating out of sync with your body can lead to weight gain, chronic diseases, and premature aging. This may be due to your body better responding to insulin or your hormone that promotes the uptake of sugar and carbohydrates to your tissues during the morning. If more food is consumed later in the day, it is harder for your body to take up the sugars which can lead to insulin insensitivity. This is associated with Type 2 diabetes. This can best be combated by eating based on your food clock!

This approach also works for when you should take your nutritional supplements since they may work better when providing you with more nutrients during a certain time of day. There are specific times when they should be taken to support your sleep and energy patterns. The key to using nutritional supplements is to be consistent and take them when it is convenient for you. This is a better approach than taking them at different times each day which could affect your activity level.

Which dietary supplements are right for me?4,5,7

There are a variety of dietary supplements available and the best ones for you depend on your needs and health conditions. Talk to your provider or pharmacist to determine which supplements may best benefit your health. Listed below are some common supplements for health conditions and the best time to take them based on chrononutrition.

Fish Oil – Fish oil is a source of omega 3 fatty acids that are needed for your body’s muscles and cell growth. It contains two omega 3 acids called docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) that are commonly found in oysters, salmon, and trout. Fish oil is helpful in reducing inflammation for conditions like rheumatoid arthritis and high cholesterol while promoting heart health. The most common side effects include burping and nausea, but it can best be managed by following the circadian diet. Taking it with food twice a day decreases these effects.

Vitamin D – Vitamin D supports your bones, muscles, heart, calcium absorption, and immune system. It is even obtained naturally from sunlight exposure. It can be obtained from dairy products, orange juice, mushrooms, and fish. Since it can be obtained from sunlight, it is best to take it in the morning with breakfast to mirror sunlight exposure.

Calcium – Calcium is commonly used to support strong bones, nerve function, and reduce the risks of cancers like breast and prostate cancer. Dietary sources of calcium include milk, cheese, yogurt, okra, and kale. If it is taken with Vitamin D, it enhances the ability of calcium to be absorbed in your body while being taken with iron decreases its absorption.

Magnesium – Magnesium is important for muscle and nerve function, blood sugar regulation, and bone health. Food sources include whole grains, nuts, beans, and spinach. When taken at night, it promotes a more peaceful sleep by stimulating neurotransmitters that relax your body at night. A common side effect is an upset stomach, so it is best to take with food.

Vitamin B complex – Vitamin B complex includes the following eight types of vitamin B: thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folic acid (B9), and cobalamin (B12). Vitamin B is found in a variety of foods like poultry, fish, eggs, broccoli, bananas, and whole grains. It supports your overall energy, mood, appetite, digestion, growth of red blood cells, eye sight, nerve function, hormone production, and muscle tone. It is also used by pregnant women to reduce the risk of birth defects and preeclampsia. Since it helps energize you, it may be better to take it earlier in the day to avoid sleeping issues. It is best taken with food to increase absorption.

Probiotics – Probiotics contain the good bacteria that line your digestive tract to promote digestion and immune functions. They can be used to decrease inflammation, improve irritable bowel syndrome (IBS), and protect against an upset stomach. They are commonly taken when you have an infection and are prescribed an antibiotic. Antibiotics can cause an upset stomach because they harm your good and bad bacteria, so probiotics replenish the good bacteria. They should be taken 30 minutes before or during a meal to maximize the ability of the probiotics to reach the gut quickly. They also interact with antibiotics since antibiotics can decrease the concentration of probiotics, so they should be spaced out by at least two hours.

Are there any dangers with nutritional supplements?3

Remember, just because a product says “natural,” it does not mean that it is safe. Its safety can be affected by how much you take and how it works. Nutritional supplements can interact with prescription or over-the-counter medications you are taking. Before taking nutritional supplements, talk with your provider or pharmacist to make sure they are right for your nutritional needs or health conditions.


  1.  Nutritional supplements market report, 2021-2028. Grandview research website. Accessed September 12, 2021.
  2. The truth behind the top 10 dietary supplements. WebMD website. Accessed September 12, 2021.
  3. What you need to know. NIH website. Accessed September 12, 2021.
  4. Chrononutrition: Is there a “best time” to take nutritional supplements? Metagenics website. Accessed September 12, 2021.
  5. Chrono-nutrition: Personalizing which supplements to take and when. Nutri-facts website. Accessed September 12, 2021.
  6. How to guide chrono-nutrition. Humanos website. Accessed September 12, 2021.
  7. Why is vitamin B complex important, and where do I get it? Healthline website. Accessed September 12, 2021.