As we continue to navigate the winter season, we have all likely experienced getting sick or had to care for loved ones recently. In light of the last 3 years, we have had to consider the health of our immunity and taken many steps to be proactive in our personal care. One of these areas of concern is nutrition, which is always a considerable piece to the puzzle of our health. Most people are familiar with nutrients that play a role in immune health such as Vitamin D, Vitamin C, Zinc, and others, but the role of hydration during illness does not often come to the forefront of our mind until it’s too late.
Proper hydration is a balancing act that requires not just taking in enough fluids; it also requires the orchestra of electrolytes working in concert to allow for fluids to be retained and be functional. Furthermore, during times of illness thirst can be impacted, as well as fluid loss increased, which can multiply the effects of how we feel and delay proper recovery. Let’s take a look at some of the ways improper hydration can negatively affect not only immune health but overall health as well.
Because every cell in your body requires fluid as a medium by which to function properly, it should come as no surprise that immune cells also necessitate proper hydration. However, fluids in and of themselves are not sufficient to maintain fluid status. Electrolytes are essential for maintaining fluid balance inside the cells, as well as fluid between them and in the blood supply. When either not enough fluids, or not enough electrolytes, or even an imbalance of electrolytes are consumed, the risk of dehydration can be impacted. Proper hydration is critical for cell membrane stability, immune cell activation and circulation, and especially nervous system transmission which are all functions the immune system needs to perform properly. Research suggests that even mild dehydration (defined as less than 3% loss in body weight from fluid depletion) can lead to lowered immune system functionality. (1) This is astounding, as many simple activities such as exercise or even just living in a warmer climate can encourage the loss of fluids at a higher rate than normal. Research also suggests that dehydration can decrease the function of antimicrobial proteins, which are one of the front line defense systems we have to maintain health. (2) Typically, thirst is one of the first indicators telling us we need more fluid. Unfortunately those who would be most impacted during illness, such as the elderly, often have a lowered sense of thirst to begin with. Simply put, although we have natural mechanisms that help remind us of the need to stay hydrated, being proactive during times of immune stress is important to provide our body with the tools they need.
When considering ways to stay hydrated during illness, its important to remember three concepts:
- Overall Fluid Intake: the amount of fluid from Liquids and Foods coming in from the diet
- Overall Electrolyte Intake: the total amount of electrolyte minerals coming in from those sources
- The Balance of Electrolytes: The ratios of electrolytes minerals needed to optimize their function
1) How much water you need to drink can vary quite a bit, however it is important to remember that your body is typically made up of 55-60% water. (3) Minimizing losses, especially during times of sickness is imperative during this time. You may have heard that 8 cups of water a day is needed, or even that you need up to a gallon a day, but experts suggest that minimally 4-6 cups (32-48oz) is a baseline to build off of, with more likely yielding additional benefits. (4, 5) It is important to note here that how much you need to drink is contextual, which is why it can’t be the only factor considered for staying hydrated. As you consume to replace lost fluids, they need to contain electrolytes as they are also lost.
2) While additional fluid intake can be beneficial your electrolyte status will regulate how it’s used, and what stays and what goes on a daily basis. Overall electrolyte needs are enormous when compared to other micronutrients like vitamins and most minerals. Whereas you require only a couple hundred milligrams of almost all other micronutrients, you require 1000’s of milligrams combined of the big 4 electrolyte minerals (sodium, potassium, calcium, and magnesium). Consider Potassium, where the established Adequate Intake level is set at 4,700mg/day. Compare this to sodium, where the AI is set at 1500mg/day. These two electrolytes alone play the most critical role in maintaining fluid balance in the body and MUST be consumed regularly to avoid dehydration. Calcium and Magnesium must also be considered here and their requirements are 1300mg/day and 420mg/day, respectfully. When these are not consumed in adequate amounts, drinking more water only dilutes their concentration in the body and can actually inhibit overall fluid function and even contribute to dehydration, as strange at that sounds. This is why it’s generally recommended to NOT consume only reverse osmosis water which has no minerals, and it’s also why most commercial water is fortified with at least some minerals. Altogether, maintaining your electrolyte intake is as important as fluid intake, but even then it is not sufficient for contributing to optimal hydration.
3) If we only considered how much total electrolyte minerals we consume in our diet, most individuals would be close to the amount needed. If we look closer and actually considered the balance of them in the average person’s diet, the story becomes much different. The best way to explain this is to consider what the optimal ratios are between the big 4 electrolytes. It is suggested that we should consume around twice the amount of Potassium in the diet as we do Sodium (2:1), and yet the average person consumes only half of our potassium needs and almost twice the sodium needs. (6) Additionally, research suggests that we should consume calcium and magnesium at no more than a 3:1 ratio yet we know that we only consume about half of magnesium requirements. (7) These ratios are important, as all the electrolytes in the diet work together, and rely on each other, to facilitate the movement and retention of fluids. Currently in our culture a lot of work needs to be done in order to restore this balance and that begins with the diet. Limiting high sodium processed foods while increasing potassium rich foods is a good first step, while considering more whole foods in general will support increasing our magnesium intake. When looking to supplement with electrolyte minerals, look for those that provide the diversity and ratios needed to help restore this balance. Lastly, consider products that contain higher amounts of Potassium and Magnesium, as those are the two most likely needed to bring your levels back in line. There are many more nutritious benefits that flow from these simple changes, but electrolyte balance for hydration is one you will likely feel immediately.
All of this is to say that you can drink all the fluids you want, but if you do not consume either enough electrolytes or in the right balance, then you are preventing your body from using and retaining that fluid correctly which impacts hydration and ultimately immune function.