Fiber and Sodium

Fiber and sodium are micronutrients that can have a big impact for most people, and deserve to be talked about separately from other micronutrients.

Fiber is a type of carbohydrate that adds bulk to our food, helps to feed our microflora in the gut, keeps food waste moving efficiently through our system, and is often correlated with a lifestyle that reduces risk of heart disease. Within the context of a healthy diet, most people should shoot for at least 10-15g of fiber per 1000 calories consumed. While fiber supplements like psyllium husk are marketed as a solution, it is not difficult to get this much fiber from whole foods like whole grains, legumes, vegetables and fruits, unless you're restricting total carbohydrates on the plan you've chosen.

'Net carbs' is a concept that some low-carb type nutrition plans (like keto) use to encourage consumption of higher fiber and lower starch/sugar carbohydrates to reach a person's goals. People counting net carbs do not count fiber toward the daily carb goals. As long as you are on the same page with your nutrition coach or medical professional about how you are expected to count your carbs, and you are tracking consistently, what matters to your body is that you are getting adequate fiber to keep your gut happy and keep your 'movements' moving.

Specific examples of high fiber foods include whole grains (like 100% whole wheat bread, oats, buckwheat, barley, and rye), legumes and pulses (like beans, peas, lentils), avocados, citrus fruits (like oranges and grapefruit), root vegetables (like carrots, potatoes, and sweet potatoes), raw mushrooms, nuts and seeds.

Let's move on to sodium. Sodium is a nutrient we need - it's found in every tissue of our body - but eating too much is thought to be a risk factor for heart disease. Because it plays a role in maintaining heart rate and our blood pressure increases when our kidneys retain water to maintain a safe concentration of sodium in our blood (or can drop rapidly if we're focused on avoiding it), it's good to keep an eye on sodium intake. It's never too early or too late to change your food choices. The American Heart Association suggests that most adults should limit sodium intake to 2300 mg/day and work to bring it down closer to 1500 mg/day. If you're an athlete or you have a labor-intense job and you sweat heavily, or if you're predisposed to low blood pressure, be sure to talk to your medical team about where your lower limit should be, as your sodium needs may be higher than for most people. Note that if you're pursuing a weight loss goal, keeping your sodium intake on the lower end and also consistent from day to day will help to mitigate weight fluctuations from water retention, since the body naturally retains water to maintain a safe concentration of sodium in the bloodstream. It can take two or three days for sodium-driven water retention to clear your system, so if you want a true reflection of your weight loss progress, avoid salty snacks right before your weigh-in.

Practical ways to reduce sodium in your diet include limiting processed foods and foods prepared in restaurants, or, if eating out is a big part of your lifestyle, requesting that your food be made without added salt (even fast food restaurants can accommodate 'fries made to order, no salt added' if you ask - you can't take the salt out of the burgers or nuggets, so just do what you can where you can when you can and improve your health one choice at a time). Look to see if the restaurant has a "heart healthy" menu section, which should include options that are lower in both salt and saturated fat.

When choosing packaged foods, compare food labels and choose the lower salt version (even popular cereals like bran flakes can pack more sodium than you might expect), or pick unsalted or 'reduced sodium' options whenever there is an option. You can always add salt at home, and chances are, when you add it last, you'll use less of it to taste 'salty enough'. Choose frozen (without pre-made sauces) or fresh vegetables over canned, but if you're used to eating canned veggies, look for those lower salt option. If you choose to can your own food, most pressure-canning recipes used for basic veggies are salt-optional, so cutting salt in half or removing it altogether does not create a food safety risk as long as you're using safe-tested home canning recipes (more on that in a future post). If you participate in food drives, maybe choose salt-free and low-salt options to donate.

At the grocery store, opt for low-salt/reduced-salt options if deli meat and cheese are something you normally eat. Most grocery store delis at least have low or no-salt turkey breast, and many have lower salt ham, roast beef, and sometimes even bologna. Cheeses aren't often marked as lower sodium, but the lowest sodium types (by their nature) are what we think of in the US as Swiss style cheeses (Swiss, baby Swiss, Alpine Lace, and Gruyere, for example). Choose meat and seafood that hasn't been cured or marinated and add your own seasoning at home, or limit the use of cured meat - one tip from the Mediterranean way of eating is to rethink the use of cured meat. Try thinking of bacon, ham, and sausage more as a seasoning than as an entrée.

The impact of sodium and fiber on day-to-day weight fluctuations

If you're watching your weight, you'll notice that weight is not usually the same from day to day or even throughout the day. That is completely normal. Read it again, it is completely normal. There are a few factors that play in; fiber and sodium intake during the previous day or two (sometimes three) can be big ones. When sodium is unusually high, the kidneys are cued to retain water to maintain a safe concentration of sodium in the blood stream. Retained water makes you heavier (and is part of the why/how of higher blood pressure with high sodium intake - which does wear on your blood vessels over time), and assuming you go back to normal-for-you sodium intake over the next few days, it all flushes out and your weight is also back to normal.

With fiber, it's an opposite sort of effect; unusually low fiber intake can result in temporarily higher weight, as fiber helps keep things moving and if you're not eating enough, your waste elimination systems are moving slower and accumulating more waste. Digestive waste (yes, we're talking about poop) gets counted with the rest of you when you weigh yourself - and if you're using a body composition scale, the density is more like fat than muscle, so it also looks like you've gained fat weight, so don't let that panic you if you know you haven't had a good BM in a few days.

Both of these nutrients are also important for long-term health outcomes. It's never too soon - and never too late - to start being mindful of sodium and fiber intake.