How Protein and Fiber Will Change Your Body

How Protein and Fiber Will Change Your Body

I’ve looked at a lot of food logs.

I’ve seen many different styles of eating, based on the client’s age, geographic region, culture, and tastes.

But whether someone is a 60-year-old woman from the Midwest or a 30-year-old man from Brooklyn, two common themes consistently emerge:

Protein and fiber.

In many cases, people don’t eat enough of either nutrient.

Most people’s diets are excessively high in carbohydrates and fat, without the solid, slow-burning, health-promoting building blocks of protein and fiber.

It’s easy to think that this only happens when people are classically “unhealthy” – eating junk food, never rarely preparing food for themselves, living on drive-through meals, etc. But it also happens when people try to lose weight, because they often start eating less and cutting carbohydrates and other foods that they perceive to be “bad” or high in calories – this often cuts both fiber and protein from their diets. This often leaves people running hungry from meal to meal, with high levels of food cravings and symptoms like afternoon energy crashes (or late evening snack attacks).

Most Americans eat 10-15 grams of fiber per day. For women under 50, however, the goal should be at least 25 grams per day. Once you are over 50, the goal lowers slightly to 21 grams. For men, the target is even higher – 38 grams for men under 50, and 30 grams for men over 50. Obviously the average 10-15 grams per day radically undershoots the ideal.

While the need for eating more fiber is pretty clear-cut, protein can be more of a gray area in terms of public opinion. The Recommended Daily Allowance stipulates eating at least 0.8 grams of protein per kilogram of bodyweight. To figure out your minimum protein intake goal, multiply your bodyweight (in pounds) by 0.36. But this is simply the minimum – most active people need much more. The public health outlook on protein is that most Americans get enough, or even too much. But the issue is that the bulk of this intake is coming from less-ideal protein sources (like processed meats or red meats) at the expense of fiber-rich foods like beans, nuts, and seeds. Ideally, I recommend that my active female clients eat about 100-130 grams of protein per day (to support lean body mass), and that my male clients eat about 150-200 grams per day, depending on weight and muscle mass.

So why are these nutrients are so important, and how do we make sure we’re getting enough of them?

The Importance of Protein and Fiber

Eating more protein and fiber can make a profound difference in someone’s eating behaviors, their relationship with food, their physical health (especially cardiovascular health), and their physique.

What protein and fiber have in common is that they are both slow-digesting. This means that when you eat a veggie and cheese omelet with a side of oatmeal for breakfast, this meal stays in your stomach longer than, say, a bagel would.

This physically makes you feel fuller – literally, mechanically, your stomach keeps its “fullness signals” longer because it’s containing food.

But the satisfaction benefits (in dietetics they call this “satiety”) of protein and fiber go beyond mechanical fullness. It’s also related to the fact that slow-digesting foods, especially fiber, prevent large blood sugar spikes, which means that you also get to skip the resulting blood sugar “crashes.” In real-world terms, this means that you don’t get on the cravings roller coaster when you eat meals that are well-balanced. You’re likely to experience authentic hunger again when it’s time for your next meal or snack – not panicked cravings within less than a few hours.

Additionally, protein plays a significant role in “muscle protein synthesis” – the process in which your body builds and maintains muscle mass. This is important at every time of life, but is particularly important for older adults, when muscle mass is easily lost. Active people and older people should be especially attentive to regular protein intake.

This means that eating enough protein and fiber can change your eating behavior as well as your physique, even if each individual meal actually contains more calories.

Let’s say you normally have an English muffin with butter for breakfast, and that the whole meal is 200 calories. From a calorie reduction point of view, a 200-calorie breakfast is fantastic. But from a macronutrient and micronutrient point of view… not so much. In an example like this, I frequently recommend that clients have a protein like eggs (or a combination of eggs and egg whites) for breakfast with the English muffin, and also find a way to add some fiber, like adding a veggie (like broccoli) to the eggs. This is a much more filling breakfast. There’s nothing wrong with the English muffin, per se. It’s not about what it is… it’s more about what it isn’t.

Even if you end up with a 400-calorie meal instead of a 200-calorie meal, from a calorie reduction point of view, you will likely still be fine because you may be able to trim mindless eating from the rest of your day, because you’re not as hungry.

To keep the ball rolling from the example I just made, let’s explore practical ways that you can add more protein- and fiber-rich foods to your day.

Practical Ways to Increase Intake

The first rule of thumb for protein and fiber is to split up intake fairly evenly throughout the day. Instead of consuming some meals that are huge protein and fiber “bombs” and then having other meals that are scant sources, I would recommend finding easy ways to increase intake at each meal and snack.

Take a look at the two lists below and think about how you could include at least one food from each list in each meal and snack of your day…

Foods that are reliable sources of protein include:

  • Literally any meat, poultry, or fish (but from a health perspective, unprocessed animal proteins like fish and lean poultry/meats are superior choices)
  • Dairy products, especially Greek yogurt
  • Eggs and egg whites
  • Lentils and beans and related products
  • Edamame and related products
  • Protein powders and bars
  • Products that help “boost” protein intake in meals, like bean-based pastas, egg-based wraps, protein pancakes, etc.

Foods that are excellent sources of fiber include:

  • Oatmeal and other whole grains
  • Chickpeas, kidney beans, and other beans (and bean products)
  • Lentils (and lentil products)
  • Walnuts, chia seeds, and other nuts and seeds
  • Pears, apples, and other fruits with skins 
  • Strawberries, raspberries, and other berries 
  • Broccoli, Brussels sprouts and other bulky vegetables 
  • Psyllium husks
  • Sweet potato 
  • Also, weirdly, avocado! 

If you can include at least one food from each list into each meal and snack, you will probably achieve ideal protein and fiber goals without a problem. Think oatmeal with a side of yogurt and berries at breakfast. A lentil soup for lunch with spinach in it. A chicken and veggie stir fry for dinner with a side of rice. Snacks of fruit and roasted nuts and beans, and a protein shake after your workout. This will cover your bases.

For most people, you don’t need to worry about hitting extremely specific or super-high numbers. Eating 100 grams of protein isn’t necessarily better than eating 90 grams. It’s about making sure that each meal and snack has a respectable “chunk” of fiber and protein each, and doing it in ways that are sustainable and easy to make part of your habits and routines. This may mean finding packaged products that work for you – in this blog post and this blog post I mention some of my favorite recommendations.

In my opinion, some of the best additions to your diet are the ones that are heavy-hitters for both protein and fiber – foods like edamame, chickpeas, lentils, and other protein-rich legumes.

In other words, don’t try to hit your protein goals with burgers and protein shakes and your fiber goals with Metamucil. Do your best to increase your intake from whole-foods sources, and “combined” sources (like legumes) as often as possible.

What About Carbs and Calories?

But if you are carb-conscious (or calorie conscious overall), you may be concerned about the concept of adding more food into your day, especially if you are getting more fiber from carbohydrates. What about blood sugar? What about weight loss?

If you are managing conditions like Type 1 or Type 2 diabetes, it’s smart to make nutritional changes with the partnership of a registered dietitian, or your physician. You’ll want to monitor how nutrition habits affect important numbers.

But if you’re just trying to lose a little weight, eat better, or get fitter, the great likelihood is that focusing more on protein and fiber will regulate your carbohydrates and calories overall.

Eating fiber-rich carbohydrates helps to attenuate the glucose response that usually accompanies eating carbohydrates.

Furthermore, focusing more on protein and fiber often gets people to:

  • Plan their food more in advance
  • Cook more at home
  • Pack lunches
  • Look at nutrition facts on labels
  • Eat regularly and not skip meals

… and many other health-promoting behaviors that help with weight management.

Final Takeaways

The most helpful way to figure out if you are eating enough protein and fiber is to keep a food log. Just keep it in a notebook or in a document/spreadsheet on your computer. Note:

  • When you eat
  • What you eat
  • The total fiber and protein content of the meal (which you can figure out from reading labels or Google)

I would recommend that you aim for 5-10 grams of fiber per meal, and 20-30 grams of protein per meal.*

After about 5 days, you will have a strong sense if you are consistently hitting targets, if you are way off, or if you are almost there.

Do you have any questions about protein, fiber, weight management, meal planning, or something else that came up for you in this blog post? Shoot me an e-mail to ask me about it.

*The numbers should be higher for men – more like 10-15 grams of fiber per meal, and 30-50 grams of protein per meal.