Getting enough protein in your diet can help you have more toned muscles, reduce hunger, speed recovery after exercise and get more benefits. However, while it is important to maintain a healthy diet rich in this macronutrient, there are some positive and negative effects of reaching too much protein.
Most research suggests that very active people should eat between 1.2 and 2 grams of protein per kilogram of body weight. Lean meats, fish, and dairy are popular examples of foods that contain a good source of this macronutrient.
Consuming large amounts of any nutrient over a long period of time generally carries risks, as can protein. Excessive consumption can lead to an increased risk of certain health complications.
There are potential benefits of a high-protein diet for healthy people. However, it is important to understand the health problems related to excess protein in the body, especially if we maintain such a diet for a long period of time.
High-protein diets can promote weight loss, but this type of weight loss may only be short-term. Excess protein consumed is usually stored as fat, while excess amino acids are excreted. This can lead to weight gain over time, especially if we consume too many calories while trying to increase protein intake.
One study found that weight gain was significantly associated with diets in which protein replaced carbohydrates, but not when it replaced fat.
Having an excess of protein can cause bad breath, especially if we restrict the intake of carbohydrates. In one study, 40 percent of participants reported bad breath. This could be in part because the body enters a metabolic state called ketosis , which produces chemicals that give off an unpleasant fruity odor.
Brushing and flossing will not remove the odor. We can double our water intake, brush our teeth more often, and chew gum to counteract some of this effect.
High-protein diets that restrict carbohydrates are often low in fiber, thus increasing the chance of constipation . Increasing your water and fiber intake can help prevent constipation. Tracking bowel movements can be helpful.
On the other hand, eating too much dairy or processed foods, along with a lack of fiber, can cause diarrhea . This is especially true if we are lactose intolerant or consume protein sources such as fried meat, fish, and poultry. Instead, we’ll eat heart-healthy protein.
To avoid diarrhea, we will drink plenty of water, avoid caffeinated beverages, limit fried foods and excessive fat intake, and increase fiber intake.
Bloating is a very uncomfortable feeling in the stomach part of the body, where we feel like unbuttoning our pants and just not moving for a while. Bloating can occur for a number of reasons, including eating too quickly, eating foods that cause gas, or even drinking through a straw. What we may not have known is that diet, which includes too much protein, can also be a factor.
When people eat a high-protein diet, they think they will feel less bloated, but they don’t include enough high-fiber foods like fruits and vegetables or whole grains and beans (carbohydrates) and become constipated due to lack of fiber. Constipation causes an upset stomach and bloating, and people’s pants often feel tight.
The body removes excess nitrogen with fluids and water. This can leave us dehydrated even if we don’t feel more thirsty than normal. A small study with athletes found that as protein intake increased, hydration levels decreased. However, one study concluded that excess protein had minimal impact on hydration.
This risk or effect can be minimized by increasing water intake, especially if we are an active person. Regardless of protein intake, it is always important to drink plenty of water throughout the day.
Studies link high protein intake to kidney damage in healthy people, too much protein can cause damage in people with pre-existing kidney disease. This is due to excess nitrogen found in the amino acids that make up proteins. Damaged kidneys have to work harder to get rid of the extra nitrogen and waste products of protein metabolism.
Separately, one study looked at the effects of low-carbohydrate, high-protein versus low-fat diets on the kidneys. The study found that in healthy obese adults, a low-carbohydrate, high-protein diet for weight loss for two years was not associated with markedly harmful effects on kidney filtration, albuminuria, or fluid and electrolyte balance compared with a low fat diet.
If we feel that we always have to urinate, it may be due to an excess of protein. Our kidneys can only process so much protein at a time, so the excess starts to build up.
The buildup of protein in the kidneys creates a much more acidic environment in the kidneys, causing you to have to urinate all the time. Increased acid production can also cause bone and liver problems.
Side effects start with mild dehydration but can lead to the development of kidney stones, which are intensely painful. The researchers found that plant and dairy proteins had a much smaller negative effect on kidney function than non-dairy animal (meat) proteins.
Increased risk of cancer
Studies have shown that certain high-protein diets that are particularly high in red meat-based protein are linked to an increased risk of various health problems, including cancer. Eating more red and/or processed meat is associated with colorectal, breast, and prostate cancer.
In contrast, eating protein from other sources has been associated with a decreased risk of cancer. Scientists believe this may be due, in part, to hormones, carcinogenic compounds, and fats found in meat.
Eating a lot of red meat and full-fat dairy products as part of a high-protein diet can lead to heart disease. This could be related to a higher intake of saturated fat and cholesterol. According to one study, eating large amounts of red meat and high-fat dairy was shown to increase the risk of coronary heart disease in women. Eating poultry, fish, and nuts lowered the risk.
One study also showed that long-term consumption of red meat can increase trimethylamine N-oxide, a chemical produced by the gut that is linked to heart disease. The findings also showed that reducing or eliminating red meat in the diet reversed the effects.
Diets high in protein and meat can cause calcium loss. This is sometimes associated with osteoporosis and poor bone health.
A review of studies found an association between excess protein and poor bone health. However, another review found the effect of protein on bone health to be inconclusive. More research is needed to expand and conclude on these findings.
Even if we usually get eight hours of sleep every night, eating too much protein can still leave the body tired for a number of reasons. First, excessive consumption can put pressure on the kidneys, liver, and bones, causing them to work overtime. Also, eating too few carbs can really mess with our brains, keeping us from being alert, focused, and energized every day.
Since carbohydrates are the main source of energy for the brain, we probably want to increase the consumption of healthy carbohydrates, such as whole grains, fruits and vegetables, to recover the best level. Not only can this help restore energy, but we will also get more vitamins, minerals and fiber that the body needs to be healthy.
The ideal amount of daily protein to consume varies based on a number of factors, including age, gender, activity, health, total diet, and other variables. However, in most cases, the recommended daily amount of protein for adults can be calculated based on body weight.
For most adults with minimal physical activity, experts recommend consuming a minimum daily average of 0.8 grams of protein per kilogram of body weight. If we exercise primarily with weights or body weight for more than an hour most days of the week, we can eat up to 1.2 to 1.7 grams per kg of body weight each day. However, some people, including elite athletes, can eat up to 3.5g per pound of body weight without side effects.
In general, experts also believe that most healthy adults can tolerate eating 2 grams of protein per kg of body weight per day in the long term. While others believe healthy adults can safely consume even higher levels of protein regardless of activity level, this has not been extensively studied long-term.